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Search for "heterocyclic compounds" in Full Text gives 262 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.
Regioselective synthesis of heterocyclic N-sulfonyl amidines from heteroaromatic thioamides and sulfonyl azides
- Vladimir Ilkin,
- Vera Berseneva,
- Tetyana Beryozkina,
- Tatiana Glukhareva,
- Lidia Dianova,
- Wim Dehaen,
- Eugenia Seliverstova and
- Vasiliy Bakulev
Beilstein J. Org. Chem. 2020, 16, 2937–2947, doi:10.3762/bjoc.16.243
- , rich chemistry and technically useful properties of heterocyclic compounds have made them a focal point of science and industry over the years. Heterocyclic compounds including azoles and azines have been found in natural products, and they are included in the structures of nucleic acids, vitamins
- synthesis of various types of sulfur containing heterocyclic compounds [43][44][45][46][47]. This gives some promise to the development of a general and efficient method for the synthesis of N-sulfonyl amidines of heteroaromatic acids based on the reaction of heterocyclic thioamides with higly electrophilic
Graphical Abstract
Figure 1: Examples of biological activity and interesting chemical reactivity of N-sulfonyl amidines.
Figure 2: Data on the synthesis of N′-sulfonylazole-4-carboximidamides.
Scheme 1: Synthesis of 1-alkyl-N-phenyl-N'-(sulfonyl)-1H-1,2,3-triazole-4-carboximidamides 3.
Figure 3: Starting compounds.
Scheme 2: Scope for the reaction of 1-alkyl-1,2,3-triazole-4-carbothioamides 1a–d with azides 2a–f.
Scheme 3: Scope of the reaction of 5-arylamino-1,2,3-triazole-4-carbothioamides 1i–l with azides 2a,c–f.
Scheme 4: Synthesis of 2-aminothiazole-4-N-sulfonyl amidines.
Scheme 5: Synthesis of N-sulfonyl amidines of isoxazolylcarboxylic acid.
Scheme 6: Synthesis of bis(sulfonyl amidines) 3aj–an.
Scheme 7: Plausible mechanism for the reaction of heterocyclic thioamides with sulfonyl azides.
Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives
- Emese Gal,
- Luiza Gaina,
- Hermina Petkes,
- Alexandra Pop,
- Castelia Cristea,
- Gabriel Barta,
- Dan Cristian Vodnar and
- Luminiţa Silaghi-Dumitrescu
Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242
- heterocyclic compounds, the use of ultrasound irradiation became a powerful tool by proving to be superior in terms of reaction rates, yields, and the purity of the products as compared to traditional convective heating methods [2]. Sonochemical syntheses can be successfully performed in homogeneous media
Graphical Abstract
Scheme 1: Synthesis of α-amino-acetonitrile derivatives. Reaction conditions: Aldimine (1 equiv), TMSCN (1 eq...
Figure 1: Crystal structure of 2-phenothiazinyl-2-(p-tolylamino)acetonitrile 2a. a) ORTEP plot and b) crystal...
Figure 2: SEM images recorded at 200× for the raw reaction product 2b obtained through a) ultrasound-assisted...
Figure 3: SEM image recorded at 200× for the raw reaction product 2c obtained through a) ultrasound-assisted ...
A novel and robust heterogeneous Cu catalyst using modified lignosulfonate as support for the synthesis of nitrogen-containing heterocycles
- Bingbing Lai,
- Meng Ye,
- Ping Liu,
- Minghao Li,
- Rongxian Bai and
- Yanlong Gu
Beilstein J. Org. Chem. 2020, 16, 2888–2902, doi:10.3762/bjoc.16.238
- -Cu-promoted conditions as well, and gave the product 4o in 65% yield. The successful attempts in the three-component reaction of 4-aminoindoles (1a), alkynes and aldehydes indicate that the heterogeneous catalyst LS-FAS-Cu is competent for catalyzing nitrogen-containing heterocyclic compounds without
- catalytic system, and no desired products were determined (10p and 10q). Substituted isoquinoline derivatives are considered as an important class of N-heterocyclic compounds, showing attractive physiological, biological and pharmacological activities [41][42][43][44][45]. Therefore, the feasibility of
Graphical Abstract
Figure 1: Schematic illustration for the preparation of the catalyst in this work.
Figure 2: FTIR spectra of LS, LS-FAS, and LS-FAS-Cu.
Figure 3: Thermogravimetric weight loss of the obtained materials LS-FAS and LS-FAS-Cu.
Figure 4: FSEM imagine of LS-FAS-Cu in different scale label a) 1 μm, b) 200 nm; FTEM images of LS-FAS-Cu in ...
Figure 5: XPS spectra of LS-FAS-Cu in the regions of C 1s, O 1s, Cu 2p3/2 and Cu LMM (inset).
Scheme 1: Substrate scope of LS-FAS-Cu catalyzed three-component reactions of 4-aminoindoles, alkynes and ald...
Figure 6: Recyclability of LS-FAS-Cu, LS-FM-Cu and Resin-Cu in the reaction between compounds 1a, 2a and 3a.
Asymmetric Mannich reactions of (S)-N-tert-butylsulfinyl-3,3,3-trifluoroacetaldimines with yne nucleophiles
- Ziyi Li,
- Li Wang,
- Yunqi Huang,
- Haibo Mei,
- Hiroyuki Konno,
- Hiroki Moriwaki,
- Vadim A. Soloshonok and
- Jianlin Han
Beilstein J. Org. Chem. 2020, 16, 2671–2678, doi:10.3762/bjoc.16.217
- relevant heterocyclic compounds [20][21][22][23][24]. Thus, fluorinated propargylamine, in particular, chiral trifluoromethylpropargylamine, should be considered of great research interest due to the apparently advantageous pharmaceutical profile of CF3-containing drugs [25][26]. For example, DPC 961
Graphical Abstract
Figure 1: Anti-HIV compound containing a trifluoromethylpropargylamine moiety.
Scheme 1: Literature-known methods (a and b) and the here reported (c) approach for the synthesis of α-triflu...
Scheme 2: Substrate scope study. Reaction conditions: arylethyne 2 (0.39 mmol), imine 1 (0.3 mmol), LiHMDS (0...
Figure 2: ORTEP diagram showing of the minor product of 3a.
Figure 3: Mode of nucleophilic attacks A and B.
Scheme 3: Large-scale application of the reaction.
Scheme 4: Removal of the chiral auxiliary.
Regiodivergent synthesis of functionalized pyrimidines and imidazoles through phenacyl azides in deep eutectic solvents
- Paola Vitale,
- Luciana Cicco,
- Ilaria Cellamare,
- Filippo M. Perna,
- Antonio Salomone and
- Vito Capriati
Beilstein J. Org. Chem. 2020, 16, 1915–1923, doi:10.3762/bjoc.16.158
- °C) in the presence or absence of bases (Et3N). Keywords: deep eutectic solvents; imidazoles; phenacyl azides; phenacyl halides; pyrimidines; Introduction In a world with dwindling petroleum resources, the setting up of more and more sustainable routes for the preparation of heterocyclic compounds
Graphical Abstract
Scheme 1: One-pot synthesis of 2,5-diarylpyrazines (A) (path a) or 2-aroyl-(4 or 5)-aryl-(1H)-imidazoles (B) ...
Scheme 2: Transformation of phenacyl bromide (1a) in ChCl/Gly into phenacyl azide (2a) and 2-benzoyl-(4 or 5)...
Scheme 3: Synthesis of 2-aroyl-(4 or 5)-aryl-(1H)-imidazoles 3. Scope of the reaction. Typical conditions: 1 ...
Scheme 4: Proposed mechanism for the formation of 2-aroyl-(4 or 5)-aryl-(1H)-imidazoles 3/3' from α-phenacyl ...
Scheme 5: Proposed mechanism for the formation of 2-benzoyl-(4 or 5)-phenyl-(1H)-imidazoles 3a/3a' and 2,4-di...
Scheme 6: Scope of the synthesis of 2,4-diaroyl-6-arylpyrimidines 7. Typical conditions: 2 (0.3 mmol), Et3N (...
Stereoselective Biginelli-like reaction catalyzed by a chiral phosphoric acid bearing two hydroxy groups
- Xiaoyun Hu,
- Jianxin Guo,
- Cui Wang,
- Rui Zhang and
- Victor Borovkov
Beilstein J. Org. Chem. 2020, 16, 1875–1880, doi:10.3762/bjoc.16.155
- -tetraphenylbutanetetraol; chiral phosphoric acid; Introduction Dihydropyrimidinethiones (DHPMs) are an important class of heterocyclic compounds featuring in a large number of natural and artificial compounds possessing various biological activities, and serving as key intermediates for the synthesis of medical drugs [1
Graphical Abstract
Scheme 1: Synthesis of chiral phosphoric acid 3.
Scheme 2: Synthesis of methylated chiral phosphoric acid 7.
Scheme 3: Control experiment with catalyst 7.
Figure 1: A plausible chiral transition-state structure in the Biginelli-like reaction catalyzed by phosphori...
On the hydrolysis of diethyl 2-(perfluorophenyl)malonate
- Ilya V. Taydakov and
- Mikhail A. Kiskin
Beilstein J. Org. Chem. 2020, 16, 1863–1868, doi:10.3762/bjoc.16.153
- ., pharmacologically active substances [1][2][3][4][5], in asymmetric synthesis and catalysis [6][7][8], as precursors of heterocyclic compounds [9][10][11], as ligands in coordination chemistry [12][13][14][15][16] and for other applications [17][18]. Incorporation of fluorine atoms into an organic molecule is known
Graphical Abstract
Figure 1: Phenylmalonic acids.
Scheme 1: Synthesis of diethyl 2-phenylmalonate (4).
Scheme 2: Synthesis of diethyl 2-(perfluorophenyl)malonate (3).
Figure 2: Esters of fluorine-substituted 2-phenylmalonic acids.
Scheme 3: Hydrolysis of diethyl 2-(perfluorophenyl)malonate (3).
Figure 3: Molecular structure of 2-(perfluorophenyl)acetic acid (12).
Scheme 4: Formation of 2-(perfluorophenyl)acetic acid (12).
When metal-catalyzed C–H functionalization meets visible-light photocatalysis
- Lucas Guillemard and
- Joanna Wencel-Delord
Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147
- heterocyclic compounds in decreased yields. Once again, the use of Ru-based photocatalyst in combination with molecular oxygen as a terminal oxidant was crucial in this cyclization/C–H functionalization pathway (Figure 18). The classical C–H activation cycle involves an initial amide-directed ortho-metalation
- N-heterocyclic compounds such as phenanthridine, carbazole, and dibenzo[b,d]azepine. Simultaneously, Guo’s group published the arylation of nucleosides bearing a purine moiety. The transformation was regioselective and tolerated various substituents at the N9 position of the purine, including sugar
Graphical Abstract
Figure 1: Concept of dual synergistic catalysis.
Figure 2: Classification of catalytic systems involving two catalysts.
Figure 3: General mechanism for the dual nickel/photoredox catalytic system.
Figure 4: General mechanisms for C–H activation catalysis involving different reoxidation strategies.
Figure 5: Indole synthesis via dual C–H activation/photoredox catalysis.
Figure 6: Proposed mechanism for the indole synthesis via dual catalysis.
Figure 7: Oxidative Heck reaction on arenes via the dual catalysis.
Figure 8: Proposed mechanism for the Heck reaction on arenes via dual catalysis.
Figure 9: Oxidative Heck reaction on phenols via the dual catalysis.
Figure 10: Proposed mechanism for the Heck reaction on phenols via dual catalysis.
Figure 11: Carbazole synthesis via dual C–H activation/photoredox catalysis.
Figure 12: Proposed mechanism for the carbazole synthesis via dual catalysis.
Figure 13: Carbonylation of enamides via the dual C–H activation/photoredox catalysis.
Figure 14: Proposed mechanism for carbonylation of enamides via dual catalysis.
Figure 15: Annulation of benzamides via the dual C–H activation/photoredox catalysis.
Figure 16: Proposed mechanism for the annulation of benzamides via dual catalysis.
Figure 17: Synthesis of indoles via the dual C–H activation/photoredox catalysis.
Figure 18: Proposed mechanism for the indole synthesis via dual catalysis.
Figure 19: General concept of dual catalysis merging C–H activation and photoredox catalysis.
Figure 20: The first example of dual catalysis merging C–H activation and photoredox catalysis.
Figure 21: Proposed mechanism for the C–H arylation with diazonium salts via dual catalysis.
Figure 22: Dual catalysis merging C–H activation/photoredox using diaryliodonium salts.
Figure 23: Direct arylation via the dual catalytic system reported by Xu.
Figure 24: Direct arylation via dual catalytic system reported by Balaraman.
Figure 25: Direct arylation via dual catalytic system reported by Guo.
Figure 26: C(sp3)–H bond arylation via the dual Pd/photoredox catalytic system.
Figure 27: Acetanilide derivatives acylation via the dual C–H activation/photoredox catalysis.
Figure 28: Proposed mechanism for the C–H acylation with α-ketoacids via dual catalysis.
Figure 29: Acylation of azobenzenes via the dual catalysis C–H activation/photoredox.
Figure 30: C2-acylation of indoles via the dual C–H activation/photoredox catalysis.
Figure 31: Proposed mechanism for the C2-acylation of indoles with aldehydes via dual catalysis.
Figure 32: C2-acylation of indoles via the dual C–H activation/photoredox catalysis.
Figure 33: Perfluoroalkylation of arenes via the dual C–H activation/photoredox catalysis.
Figure 34: Proposed mechanism for perfluoroalkylation of arenes via dual catalysis.
Figure 35: Sulfonylation of 1-naphthylamides via the dual C–H activation/photoredox catalysis.
Figure 36: Proposed mechanism for sulfonylation of 1-naphthylamides via dual catalysis.
Figure 37: meta-C–H Alkylation of arenes via visible-light metallaphotocatalysis.
Figure 38: Alternative procedure for meta-C–H alkylation of arenes via metallaphotocatalysis.
Figure 39: Proposed mechanism for meta-C–H alkylation of arenes via metallaphotocatalysis.
Figure 40: C–H borylation of arenes via visible-light metallaphotocatalysis.
Figure 41: Proposed mechanism for C–H borylation of arenes via visible-light metallaphotocatalysis.
Figure 42: Undirected C–H aryl–aryl cross coupling via dual gold/photoredox catalysis.
Figure 43: Proposed mechanism for the undirected C–H aryl–aryl cross-coupling via dual catalysis.
Figure 44: Undirected C–H arylation of (hetero)arenes via dual manganese/photoredox catalysis.
Figure 45: Proposed mechanism for the undirected arylation of (hetero)arenes via dual catalysis.
Figure 46: Photoinduced C–H arylation of azoles via copper catalysis.
Figure 47: Photo-induced C–H chalcogenation of azoles via copper catalysis.
Figure 48: Decarboxylative C–H adamantylation of azoles via dual cobalt/photoredox catalysis.
Figure 49: Proposed mechanism for the C–H adamantylation of azoles via dual catalysis.
Figure 50: General mechanisms for the “classical” (left) and Cu-free variant (right) Sonogoshira reaction.
Figure 51: First example of a dual palladium/photoredox catalysis for Sonogashira-type couplings.
Figure 52: Arylation of terminal alkynes with diazonium salts via dual gold/photoredox catalysis.
Figure 53: Proposed mechanism for the arylation of terminal alkynes via dual catalysis.
Figure 54: C–H Alkylation of alcohols promoted by H-atom transfer (HAT).
Figure 55: Proposed mechanism for the C–H alkylation of alcohols promoted by HAT.
Figure 56: C(sp3)–H arylation of latent nucleophiles promoted by H-atom transfer.
Figure 57: Proposed mechanism for the C(sp3)–H arylation of latent nucleophiles promoted by HAT.
Figure 58: Direct α-arylation of alcohols promoted by H-atom transfer.
Figure 59: Proposed mechanism for the direct α-arylation of alcohols promoted by HAT.
Figure 60: C–H arylation of amines via dual Ni/photoredox catalysis.
Figure 61: Proposed mechanism for the C–H arylation of amines via dual Ni/photoredox catalysis.
Figure 62: C–H functionalization of nucleophiles via excited ketone/nickel dual catalysis.
Figure 63: Proposed mechanism for the C–H functionalization enabled by excited ketones.
Figure 64: Selective sp3–sp3 cross-coupling promoted by H-atom transfer.
Figure 65: Proposed mechanism for the selective sp3–sp3 cross-coupling promoted by HAT.
Figure 66: Direct C(sp3)–H acylation of amines via dual Ni/photoredox catalysis.
Figure 67: Proposed mechanism for the C–H acylation of amines via dual Ni/photoredox catalysis.
Figure 68: C–H hydroalkylation of internal alkynes via dual Ni/photoredox catalysis.
Figure 69: Proposed mechanism for the C–H hydroalkylation of internal alkynes.
Figure 70: Alternative procedure for the C–H hydroalkylation of ynones, ynoates, and ynamides.
Figure 71: Allylic C(sp3)–H activation via dual Ni/photoredox catalysis.
Figure 72: Proposed mechanism for the allylic C(sp3)–H activation via dual Ni/photoredox catalysis.
Figure 73: Asymmetric allylation of aldehydes via dual Cr/photoredox catalysis.
Figure 74: Proposed mechanism for the asymmetric allylation of aldehydes via dual catalysis.
Figure 75: Aldehyde C–H functionalization promoted by H-atom transfer.
Figure 76: Proposed mechanism for the C–H functionalization of aldehydes promoted by HAT.
Figure 77: Direct C–H arylation of strong aliphatic bonds promoted by HAT.
Figure 78: Proposed mechanism for the C–H arylation of strong aliphatic bonds promoted by HAT.
Figure 79: Direct C–H trifluoromethylation of strong aliphatic bonds promoted by HAT.
Figure 80: Proposed mechanism for the C–H trifluoromethylation of strong aliphatic bonds.
Et3N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties
- Dharmender Singh,
- Vipin Kumar and
- Virender Singh
Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146
- bioactive natural products and pharmaceutical drugs [20][21][22]. Thioaurones (2-benzylidene benzo[b]thiophen-3(2H)-one) are sulfur-containing heterocyclic compounds, an important subclass of flavonoids which were first introduced by O’Sullivan in 1977 [23]. Specifically, thioaurones and their analogs show
Graphical Abstract
Figure 1: Representative examples of some commercial drugs and biologically active alkaloids.
Scheme 1: Synthesis of β-carboline-linked 2-nitrochalcones.
Scheme 2: Synthesis of β-carboline-linked benzothiophenone frameworks.
Scheme 3: Comparison of outcome of one-pot vs two-pot approach.
Scheme 4: One-pot synthesis of β-carboline C-1-tethered benzothiophenone derivatives.
Scheme 5: One-pot synthesis of β-carboline C-3-linked benzothiophenone derivatives.
Scheme 6: One-pot synthesis of β-carboline-linked benzothiophene derivative 6C.
Scheme 7: Control experiment in the presence of a radical scavenger.
Figure 2: Proposed reaction mechanism.
Figure 3: Fluorescence spectra of 2aA–nA, 2bB, 2hB, and 6C.
Figure 4: Fluorescence spectra of 4aA–gA, and 4eB.
Microwave-assisted efficient one-pot synthesis of N2-(tetrazol-5-yl)-6-aryl/heteroaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines
- Moustafa Sherief Moustafa,
- Ramadan Ahmed Mekheimer,
- Saleh Mohammed Al-Mousawi,
- Mohamed Abd-Elmonem,
- Hesham El-Zorba,
- Afaf Mohamed Abdel Hameed,
- Tahany Mahmoud Mohamed and
- Kamal Usef Sadek
Beilstein J. Org. Chem. 2020, 16, 1706–1712, doi:10.3762/bjoc.16.142
- ]. Tetrazole derivatives are a potent class of heterocyclic compounds with a wide range of biological activities owing to their unique structure. They play an important role not only as a bioisostere of the carboxylic acid group but also as flexible ligands which easily adopt to different binding modes [12][13
Graphical Abstract
Scheme 1: Previously reported methods for the synthesis of 1,3,5-triazine-2,4-diamine derivatives.
Scheme 2: One-pot synthesis of N2-(tetrazol-5-yl)-6-aryl/heteroaryl-5,6-dihydro-1,3,5-triazine-2,4-diamines 4a...
Figure 1: ORTEP diagram of compound 4i.
Scheme 3: Plausible different routes to account for the formation of products 4.
One-pot synthesis of 1,3,5-triazine-2,4-dithione derivatives via three-component reactions
- Gui-Feng Kang and
- Gang Zhang
Beilstein J. Org. Chem. 2020, 16, 1447–1455, doi:10.3762/bjoc.16.120
- heterocycles is one of the most prolific areas in organic chemistry that has drawn considerable attention from chemists due to their widespread occurrence in a variety of natural products [1][2][3][4], chemical materials [5][6], and medication [7]. Among the vast array of nitrogen-containing heterocyclic
- compounds, triazines and substituted triazines are of particular utility in drug discovery because of their broad potential biological activities [8][9]. Besides, triazinethiones also played important roles in the construction of an array of pharmacologically important compounds (Figure 1), comprising
Graphical Abstract
Figure 1: Selected examples of triazinethione-containing bioactive compounds.
Scheme 1: Strategies for the synthesis of triazinethiones.
Scheme 2: Aldehyde substrate scope of three-component reaction of aldehydes, thiourea and trimethyl orthoform...
Scheme 3: Orthoformate substrate scope of the three component reaction of benzaldehyde, thiourea, and orthofo...
Scheme 4: Gram-scale synthesis of 6aa.
Figure 2: X-ray structure of 6-(methylthio)-4-phenyl-3,4-dihydro-1,3,5-triazine-2(1H)-thione (6aa) with therm...
Scheme 5: Control experiments for investigation of the mechanism.
Scheme 6: Plausible mechanism.
Recent synthesis of thietanes
- Jiaxi Xu
Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116
- of sulfur-containing acyclic and heterocyclic compounds [10][11]. Several synthetic methods for thietanes have been developed and reviewed [12][13][14]. One traditional route is the intermolecular double substitution (cyclic thioetherification) of 1,3-dihaloalkanes, sulfonates of 3-haloalkan-1-ols
Graphical Abstract
Figure 1: Examples of biologically active thietane-containing molecules.
Figure 2: The diverse methods for the synthesis of thietanes.
Scheme 1: Synthesis of 1-(thietan-2-yl)ethan-1-ol (10) from 3,5-dichloropentan-2-ol (9).
Scheme 2: Synthesis of thietanose nucleosides 2,14 from 2,2-bis(bromomethyl)propane-1,3-diol (11).
Scheme 3: Synthesis of methyl 3-vinylthietane-3-carboxylate (19).
Scheme 4: Synthesis of 1,6-thiazaspiro[3.3]heptane (24).
Scheme 5: Synthesis of 6-amino-2-thiaspiro[3.3]heptane hydrochloride (28).
Scheme 6: Synthesis of optically active thietane 31 from vitamin C.
Scheme 7: Synthesis of an optically active thietane nucleoside from diethyl L-tartrate (32).
Scheme 8: Synthesis of thietane-containing spironucleoside 40 from 5-aldo-3-O-benzyl-1,2-O-isopropylidene-α-D...
Scheme 9: Synthesis of optically active 2-methylthietane-containing spironucleoside 43.
Scheme 10: Synthesis of a double-linked thietane-containing spironucleoside 48.
Scheme 11: Synthesis of two diastereomeric thietanose nucleosides via 2,4-di(benzyloxymethyl)thietane (49).
Scheme 12: Synthesis of the thietane-containing PI3k inhibitor candidate 54.
Scheme 13: Synthesis of the spirothietane 57 as the key intermediate to Nuphar sesquiterpene thioalkaloids.
Scheme 14: Synthesis of spirothietane 61 through a direct cyclic thioetherification of 3-mercaptopropan-1-ol.
Scheme 15: Synthesis of thietanes 66 from 1,3-diols 62.
Scheme 16: Synthesis of thietanylbenzimidazolone 75 from (iodomethyl)thiazolobenzimidazole 70.
Scheme 17: Synthesis of 2-oxa-6-thiaspiro[3.3]heptane (80) from bis(chloromethyl)oxetane 76 and thiourea.
Scheme 18: Synthesis of the thietane-containing glycoside, 2-O-p-toluenesulfonyl-4,6-thioanhydro-α-D-gulopyran...
Scheme 19: Synthesis of methyl 4,6-thioanhydro-α-D-glucopyranoside (89).
Scheme 20: Synthesis of thietane-fused α-D-galactopyranoside 93.
Scheme 21: Synthesis of thietane-fused α-D-gulopyranoside 100.
Scheme 22: Synthesis of 3,5-anhydro-3-thiopentofuranosides 104.
Scheme 23: Synthesis of anhydro-thiohexofuranosides 110, 112 and 113 from from 1,2:4,5-di-O-isopropylidene D-f...
Scheme 24: Synthesis of optically active thietanose nucleosides from D- and L-xyloses.
Scheme 25: Synthesis of thietane-fused nucleosides.
Scheme 26: Synthesis of 3,5-anhydro-3-thiopentofuranosides.
Scheme 27: Synthesis of 2-amino-3,5-anhydro-3-thiofuranoside 141.
Scheme 28: Synthesis of thietane-3-ols 145 from (1-chloromethyl)oxiranes 142 and hydrogen sulfide.
Scheme 29: Synthesis of thietane-3-ol 145a from chloromethyloxirane (142a).
Scheme 30: Synthesis of thietane-3-ols 145 from 2-(1-haloalkyl)oxiranes 142 and 147 with ammonium monothiocarb...
Scheme 31: Synthesis of 7-deoxy-5(20)thiapaclitaxel 154a, a thietane derivative of taxoids.
Scheme 32: Synthesis of 5(20)-thiadocetaxel 158 from 10-deacetylbaccatin III (155).
Scheme 33: Synthesis of thietane derivatives 162 as precursors for deoxythiataxoid synthesis through oxiraneme...
Scheme 34: Synthesis of 7-deoxy 5(20)-thiadocetaxel 154b.
Scheme 35: Mechanism for the formation of the thietane ring in 171 from oxiranes with vicinal leaving groups 1...
Scheme 36: Synthesis of cis-2,3-disubstituted thietane 175 from thiirane-2-methanol 172.
Scheme 37: Synthesis of a bridged thietane 183 from aziridine cyclohexyl tosylate 179 and ammonium tetrathiomo...
Scheme 38: Synthesis of thietanes via the photochemical [2 + 2] cycloaddition of thiobenzophenone 184a with va...
Scheme 39: Synthesis of spirothietanes through the photo [2 + 2] cycloaddition of cyclic thiocarbonyls with ol...
Scheme 40: Photochemical synthesis of spirothietane-thioxanthenes 210 from thioxanthenethione (208) and butatr...
Scheme 41: Synthesis of thietanes 213 from 2,4,6-tri(tert-butyl)thiobenzaldehyde (211) with substituted allene...
Scheme 42: Photochemical synthesis of spirothietanes 216 and 217 from N-methylthiophthalimide (214) with olefi...
Scheme 43: Synthesis of fused thietanes from quadricyclane with thiocarbonyl derivatives 219.
Scheme 44: Synthesis of tricyclic thietanes via the photo [2 + 2] cycloaddition of N-methyldithiosuccinimides ...
Scheme 45: Synthesis of tricyclic thietanes via the photo [2 + 2] cycloaddition of N-methylthiosuccinimide/thi...
Scheme 46: Synthesis of tricyclic thietanes via the photo [2 + 2] cycloaddition of N-alkylmonothiophthalimides...
Scheme 47: Synthesis of spirothietanes from dithiosuccinimides 223 with 2,3-dimethyl-2-butene (215a).
Scheme 48: Synthesis of thietanes 248a,b from diaryl thione 184b and ketene acetals 247a,b.
Scheme 49: Photocycloadditions of acridine-9-thiones 249 and pyridine-4(1H)-thione (250) with 2-methylacrynitr...
Scheme 50: Synthesis of thietanes via the photo [2 + 2] cycloaddition of mono-, di-, and trithiobarbiturates 2...
Scheme 51: Synthesis of spirothietanes via the photo [2 + 2] cycloaddition of 1,1,3-trimethyl-2-thioxo-1,2-dih...
Scheme 52: Synthesis of spirothietanes via the photo [2 + 2] cycloaddition of thiocoumarin 286 with olefins.
Scheme 53: Photochemical synthesis of thietanes 296–299 from semicyclic and acyclic thioimides 292–295 and 2,3...
Scheme 54: Photochemical synthesis of spirothietane 301 from 1,3,3-trimethylindoline-2-thione (300) and isobut...
Scheme 55: Synthesis of spirobenzoxazolethietanes 303 via the photo [2 + 2] cycloaddition of alkyl and aryl 2-...
Scheme 56: Synthesis of spirothietanes from tetrahydrothioxoisoquinolines 306 and 307 with olefins.
Scheme 57: Synthesis of spirothietanes from 1,3-dihydroisobenzofuran-1-thiones 311 and benzothiophene-1-thione...
Scheme 58: Synthesis of 2-triphenylsilylthietanes from phenyl triphenylsilyl thioketone (316) with electron-po...
Scheme 59: Diastereoselective synthesis of spiropyrrolidinonethietanes 320 via the photo [2 + 2] cycloaddition...
Scheme 60: Synthesis of bicyclic thietane 323 via the photo [2 + 2] cycloaddition of 2,4-dioxo-3,4-dihydropyri...
Scheme 61: Photo-induced synthesis of fused thietane-2-thiones 325 and 326 from silacyclopentadiene 324 and ca...
Scheme 62: Synthesis of highly strained tricyclic thietanes 328 via the intramolecular photo [2 + 2] cycloaddi...
Scheme 63: Synthesis of tri- and pentacyclic thietanes 330 and 332, respectively, through the intramolecular p...
Scheme 64: Synthesis of tricyclic thietanes 334 via the intramolecular photo [2 + 2] cycloaddition of N-vinylt...
Scheme 65: Synthesis of tricyclic thietanes 336 via the intramolecular photo [2 + 2] cycloaddition of N-but-3-...
Scheme 66: Synthesis of tricyclic thietanes via the intramolecular photo [2 + 2] cycloaddition of N-but-3-enyl...
Scheme 67: Synthesis of tetracyclic thietane 344 through the intramolecular photo [2 + 2] cycloaddition of N-[...
Scheme 68: Synthesis of tri- and tetracyclic thietanes 348, 350, and 351, through the intramolecular photo [2 ...
Scheme 69: Synthesis of tetracyclic fused thietane 354 via the photo [2 + 2] cycloaddition of vinyl 2-thioxo-3H...
Scheme 70: Synthesis of highly rigid thietane-fused β-lactams via the intramolecular photo [2 + 2] cycloadditi...
Scheme 71: Asymmetric synthesis of a highly rigid thietane-fused β-lactam 356a via the intramolecular photo [2...
Scheme 72: Diastereoselective synthesis of the thietane-fused β-lactams via the intramolecular photo [2 + 2] c...
Scheme 73: Asymmetric synthesis of thietane-fused β-lactams 356 via the intramolecular photo [2 + 2] cycloaddi...
Scheme 74: Synthesis of the bridged bis(trifluoromethyl)thietane from 2,2,4,4-tetrakis(trifluoromethyl)-1,3-di...
Scheme 75: Synthesis of the bridged-difluorothietane 368 from 2,2,4,4-tetrafluoro-1,3-dithietane (367) and qua...
Scheme 76: Synthesis of bis(trifluoromethyl)thietanes from 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithietane (3...
Scheme 77: Synthesis of 2,2-dimethylthio-4,4-di(trifluoromethyl)thietane (378) from 2,2,4,4-tetrakis(trifluoro...
Scheme 78: Formation of bis(trifluoromethyl)thioacetone (381) through nucleophilic attack of dithietane 363 by...
Scheme 79: Synthesis of 2,2-bis(trifluoromethyl)thietanes from 2,2,4,4-tetrakis(trifluoromethyl)-1,3-dithietan...
Scheme 80: Synthesis of the bridged bis(trifluoromethyl)thietane 364 from of 2,2,4,4-tetrakis(trifluoromethyl)...
Scheme 81: Synthesis of 2,4-diiminothietanes 390 from alkenimines and 4-methylbenzenesulfonyl isothiocyanate (...
Scheme 82: Synthesis of arylidene 2,4-diiminothietanes 393 starting from phosphonium ylides 391 and isothiocya...
Scheme 83: Synthesis of thietane-2-ylideneacetates 397 through a DABCO-catalyzed formal [2 + 2] cycloaddition ...
Scheme 84: Synthesis of 3-substituted thietanes 400 from (1-chloroalkyl)thiiranes 398.
Scheme 85: Synthesis of N-(thietane-3-yl)azaheterocycles 403 and 404 through reaction of chloromethylthiirane (...
Scheme 86: Synthesis of 3-sulfonamidothietanes 406 from sulfonamides and chloromethylthiirane (398a).
Scheme 87: Synthesis of N-(thietane-3-yl)isatins 408 from chloromethylthiirane (398a) and isatins 407.
Scheme 88: Synthesis of 3-(nitrophenyloxy)thietanes 410 from nitrophenols 409 and chloromethylthiirane (398a).
Scheme 89: Synthesis of N-aryl-N-(thietane-3-yl)cyanamides 412 from N-arylcyanamides 411 and chloromethylthiir...
Scheme 90: Synthesis of 1-(thietane-3-yl)pyrimidin-2,4(1H,3H)-diones 414 from chloromethylthiirane (398a) and ...
Scheme 91: Synthesis of 2,4-diiminothietanes 418 from 2-iminothiiranes 416 and isocyanoalkanes 415.
Scheme 92: Synthesis of 2-vinylthietanes 421 from thiiranes 419 and 3-chloroallyl lithium (420).
Scheme 93: Synthesis of thietanes from thiiranes 419 and trimethyloxosulfonium iodide 424.
Scheme 94: Mechanism for synthesis of thietanes 425 from thiiranes 419 and trimethyloxosulfonium iodide 424.
Scheme 95: Synthesis of functionalized thietanes from thiiranes and dimethylsulfonium acylmethylides.
Scheme 96: Mechanism for the rhodium-catalyzed synthesis of functionalized thietanes 429 from thiiranes 419 an...
Scheme 97: Synthesis of 3-iminothietanes 440 through thermal isomerization from 4,5-dihydro-1,3-oxazole-4-spir...
Scheme 98: Synthesis of thietanes 443 from 3-chloro-2-methylthiolane (441) through ring contraction.
Scheme 99: Synthesis of an optically active thietanose 447 from D-xylose involving a ring contraction.
Scheme 100: Synthesis of optically thietane 447 via the DAST-mediated ring contraction of 448.
Scheme 101: Synthesis of the optically thietane nucleoside 451 via the ring contraction of thiopentose in 450.
Scheme 102: Synthesis of spirothietane 456 from 3,3,5,5-tetramethylthiolane-2,4-dithione (452) and benzyne (453...
Scheme 103: Synthesis of thietanes 461 via photoisomerization of 2H,6H-thiin-3-ones 459.
Scheme 104: Phosphorodithioate-mediated synthesis of 1,4-diarylthietanes 465.
Scheme 105: Mechanism of the phosphorodithioate-mediated synthesis of 1,4-diarylthietanes 465.
Scheme 106: Phosphorodithioate-mediated synthesis of trisubstituted thietanes (±)-470.
Scheme 107: Mechanism on the phosphorodithioate-mediated synthesis of trisubstituted thietanes.
Scheme 108: Phosphorodithioate-mediated synthesis of thietanes (±)-475.
Scheme 109: Phosphorodithioate-mediated synthesis of 1,2-disubstituted thietanes from aldehydes 476 and acrylon...
Scheme 110: Phosphorodithioate-mediated synthesis of 1,2-disubstituted thietanes via a one-pot three-component ...
Scheme 111: Mechanism for the phosphorodithioate-mediated synthesis of 1,2-disubstituted thietanes via three-co...
Scheme 112: Phosphorodithioate-mediated synthesis of substituted 3-nitrothietanes.
Scheme 113: Mechanism on the phosphorodithioate-mediated synthesis of 1,2-disubstituted thietanes (±)-486.
Scheme 114: Asymmetric synthesis of (S)-2-phenylthietane (497).
Scheme 115: Asymmetric synthesis of optically active 2,4-diarylthietanes.
Scheme 116: Synthesis of 3-acetamidothietan-2-one 503 via the intramolecular thioesterification of 3-mercaptoal...
Scheme 117: Synthesis of 4-substituted thietan-2-one via the intramolecular thioesterification of 3-mercaptoalk...
Scheme 118: Synthesis of 4,4-disubstituted thietan-2-one 511 via the intramolecular thioesterification of the 3...
Scheme 119: Synthesis of a spirothietan-2-one 514 via the intramolecular thioesterification of 3-mercaptoalkano...
Scheme 120: Synthesis of thiatetrahydrolipstatin starting from (S)-(−)-epichlorohydrin ((S)-142a).
Scheme 121: Synthesis of 2-phenethyl-4-(propan-2-ylidene)thietane (520) from 5-bromo-6-methyl-1-phenylhept-5-en...
Scheme 122: Synthesis of 2-phenethyl-4-(propan-2-ylidene)thietane (520) directly from S-(5-bromo-6-methyl-1-phe...
Scheme 123: Synthesis of 2-alkylidenethietanes from S-(2-bromoalk-1-en-4-yl)thioacetates.
Scheme 124: Synthesis of 2-alkylidenethietanes from S-(2-bromo/chloroalk-1-en-4-yl)thiols.
Scheme 125: Synthesis of spirothietan-3-ol 548 from enone 545 and ammonium hydrosulfide.
Scheme 126: Asymmetric synthesis of the optically active thietanoside from cis-but-2-ene-1,4-diol (47).
Scheme 127: Synthesis of 2-alkylidenethietan-3-ols 557 via the fluoride-mediated cyclization of thioacylsilanes ...
Scheme 128: Synthesis of 2-iminothietanes via the reaction of propargylbenzene (558) and isothiocyanates 560 in...
Scheme 129: Synthesis of 2-benzylidenethietane 567 via the nickel complex-catalyzed electroreductive cyclizatio...
Scheme 130: Synthesis of 2-iminothietanes 569 via the photo-assisted electrocyclic reaction of N-monosubstitute...
Scheme 131: Synthesis of ethyl 3,4-diiminothietane-2-carboxylates from ethyl thioglycolate (570) and bis(imidoy...
Scheme 132: Synthesis of N-(thietan-3-yl)-α-oxoazaheterocycles from azaheterocyclethiones and chloromethyloxira...
Scheme 133: Synthesis of thietan-3-yl benzoate (590) via the nickel-catalyzed intramolecular reductive thiolati...
Scheme 134: Synthesis of 2,2-bis(trifluoromethyl)thietane from 3,3-bis(trifluoromethyl)-1,2-dithiolane.
Scheme 135: Synthesis of thietanes from enamines and sulfonyl chlorides.
Scheme 136: Synthesis of spirothietane 603 via the [2 + 3] cycloaddition of 2,2,4,4-tetramethylcyclobutane-1,3-...
Scheme 137: Synthesis of thietane (605) from 1-bromo-3-chloropropane and sulfur.
Copper-catalysed alkylation of heterocyclic acceptors with organometallic reagents
- Yafei Guo and
- Syuzanna R. Harutyunyan
Beilstein J. Org. Chem. 2020, 16, 1006–1021, doi:10.3762/bjoc.16.90
- the lactams 7, leading to the corresponding products with up to 81% yield and an enantiomeric ratio of up to 82:18 (Scheme 4B). Oxygen-containing heterocyclic compounds are ubiquitous in natural products and medicines, with many of them being chiral. Copper-catalysed ACA reactions of organometallics
- have also been employed to synthesize such chiral oxygen-containing heterocyclic compounds. Feringa’s group reported the highly regio- and enantioselective copper-catalysed direct conjugate addition of Grignard reagents to chromones and coumarins (Scheme 5) [28][29]. A variety of Grignard reagents
Graphical Abstract
Scheme 1: Copper-catalysed ACA of organometallics to piperidones. A) addition of organozinc reagents; B) addi...
Scheme 2: Copper-catalysed ACA of alkenylalanes to N-substituted-2,3-dehydro-4-piperidones.
Scheme 3: Copper-catalysed asymmetric addition of dialkylzinc reagents to N-acyl-4-methoxypyridinium salts fo...
Scheme 4: Copper-catalysed ACA of organozirconium reagents to N-substituted 2,3-dehydro-4-piperidones and lac...
Scheme 5: Copper-catalysed ACA of Grignard reagents to chromones and coumarins and further derivatisation of ...
Scheme 6: Copper-catalysed ACA of Grignard reagents to N-protected quinolones.
Scheme 7: Copper-catalysed ACAs of organometallics to conjugated unsaturated lactams.
Scheme 8: Copper-catalysed ACA of Et2Zn to 5,6-dihydro-2-pyranone.
Scheme 9: Copper-catalysed ACA of Grignard reagents to pyranone and 5,6-dihydro-2-pyranone.
Scheme 10: Copper-catalysed AAA of an organozirconium reagent to heterocyclic acceptors.
Scheme 11: Copper-catalysed ring opening of an oxygen-bridged substrate with trialkylaluminium reagents.
Scheme 12: Copper-catalysed ring opening of oxabicyclic substrates with organolithium reagents (selected examp...
Scheme 13: Copper-catalysed ring opening of polycyclic meso hydrazines.
Scheme 14: Copper-catalysed ACA of Grignard reagents to alkenyl-substituted aromatic N-heterocycles.
Scheme 15: Copper-catalysed ACA of Grignard reagents to β-substituted alkenylpyridines.
Scheme 16: Copper-catalysed ACA of organozinc reagents to alkylidene Meldrum’s acids.
Microwave-assisted efficient and facile synthesis of tetramic acid derivatives via a one-pot post-Ugi cascade reaction
- Yong Li,
- Zheng Huang,
- Jia Xu,
- Yong Ding,
- Dian-Yong Tang,
- Jie Lei,
- Hong-yu Li,
- Zhong-Zhu Chen and
- Zhi-Gang Xu
Beilstein J. Org. Chem. 2020, 16, 663–669, doi:10.3762/bjoc.16.63
- ][28][29] of complex heterocyclic compounds. Recent advance has been focused in the area toward the development of one-pot [30][31][32] Ugi cascade protocol [33][34] as the powerful synthetic strategy for the construction of increasingly complex heterocyclic compounds in the absence of metal catalysts
- existing protocols, our method is more straightforward and broadly applicable. With the mild reaction conditions, good yields, and commercial availability of the starting materials, we believe that this method represents a valuable tool for the synthesis of tetramic acid analogues and other heterocyclic
- compounds. Experimental In a similar manner as described in [38] the reactions were conducted as follows: To a magnetically stirred solution of ethyl glyoxylate (1.0 mmol) in MeOH (1.0 mL) was added the amine (0.5 mmol) in a 5 mL microwave vial, and the resulting solution was stirred at room temperature for
Graphical Abstract
Figure 1: Structures of natural tetramic acid derivatives with more clinical relevance.
Scheme 1: Synthetic strategy of compound 7a.
Scheme 2: Scope of the Ugi/Dieckmann cyclization reaction route to lead to pyrrolopyridinones 7a–l. aYield of...
Scheme 3: Postulated reaction mechanism.
Regio- and stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction
- Svetlana V. Amosova,
- Andrey A. Filippov,
- Nataliya A. Makhaeva,
- Alexander I. Albanov and
- Vladimir A. Potapov
Beilstein J. Org. Chem. 2020, 16, 515–523, doi:10.3762/bjoc.16.47
- , we are observing a new manifestation of this effect, consisting in the promotion of new rearrangements leading to the selective formation of various selenium-containing unsaturated linear and heterocyclic compounds. This effect works in 2-(bromomethyl)-1,3-thiaselenole (1) – a unique reagent, which
Graphical Abstract
Scheme 1: Possible formation of reaction products starting from 1 via seleniranium 2 or thiiranium cations 3.
Scheme 2: Unusual regio- and stereoselective nucleophilic reactions of thiaselenole 1 at two centers of the s...
Scheme 3: Reactions of thiaselenole 1 with С- and S-centered nucleophiles affording new families of linear un...
Scheme 4: The reactions of thiaselenole 1 with the formation of polyfunctionalized 2,3-dihydro-1,4-thiaseleni...
Scheme 5: The synthesis of new 1,3-thiaselenole ensembles by reactions of thiaselenole 1 with mercapto benzaz...
Scheme 6: The formation of product 4 via compound 5 by the reaction of thiaselenole 1 with potassium selenocy...
Figure 1: Monitoring the reaction of thiaselenole 1 with KSeCN by 1H NMR spectroscopy (in accordance with the...
Scheme 7: The reaction pathway for the formation of compounds 4 and 5.
Scheme 8: Synthesis of new ensembles of 1,3-thiaselenol-2-ylmethyl selenides 6a–l (77Se NMR data are included...
Scheme 9: The synthesis of vinyl selenides 7a,b through nucleophilic addition of 1,3-thiaselenol-2-ylmethylse...
Scheme 10: One-pot synthesis of diselenide 8 from thiaselenole 1 (77Se NMR data are included).
Scheme 11: Synthesis of compounds 6a–j from diselenide 8.
Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A
- Qiao Li,
- Chen Zhuang,
- Donghua Wang,
- Wei Zhang,
- Rongxuan Jia,
- Fengxia Sun,
- Yilin Zhang and
- Yunfei Du
Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291
- ; Introduction The chromone system and its derivatives are an important class of heterocyclic compounds, the skeleton of which widely exists in a variety of natural products and medicinal agents [1][2][3]. It was found that chromone derivatives exhibit a wide range of pharmacological effects, including
Graphical Abstract
Figure 1: Biologically active chromone derivatives.
Scheme 1: Methods for the synthesis of chromones via dehydrogenative oxidation of chromanones.
Scheme 2: Substrate scope studies. Reaction conditions: 1 (1.0 mmol), PhIO (2.0 mmol), DMF (6 mL), rt. Isolat...
Scheme 3: Control experiments for mechanistic studies.
Scheme 4: Proposed reaction mechanism.
Scheme 5: Application of the reported method to the synthesis of frutinone A.
Diversity-oriented synthesis of spirothiazolidinediones and their biological evaluation
- Sambasivarao Kotha,
- Gaddamedi Sreevani,
- Lilya U. Dzhemileva,
- Milyausha M. Yunusbaeva,
- Usein M. Dzhemilev and
- Vladimir A. D’yakonov
Beilstein J. Org. Chem. 2019, 15, 2774–2781, doi:10.3762/bjoc.15.269
- inducers in the HeLa, Hek293, U937, Jurkat, and K562 cell lines. Keywords: apoptosis; biologically active; [2 + 2 + 2] cycloaddition; flow cytometry; spiro thiazolidinedione; Introduction Heterocyclic compounds play a vital role in the metabolism of all living cells. Thus, most of the biologically active
- and pharmaceutically important compounds consist of heterocycles [1][2][3][4]. Especially, thiazolidinediones (TZDs) are important heterocyclic compounds. In 1954, Visentini reported the first ever pharmacological evaluation of a thiazolidinedione derivative, i.e., its anti-TB activity [3]. The
Graphical Abstract
Scheme 1: Conventional method of synthesis of thiazolidine-2,4-dione derivatives.
Scheme 2: [2 + 2 + 2] Cyclotrimerization of N-methylthiazolidinedione.
Scheme 3: Unexpected product 5b obtained in the attempted NH-protection of thiazolidinedione with (Boc)2O.
Figure 1: Comparison of 13C NMR values of 9 and 5b.
Scheme 4: [2 + 2 + 2] Cyclotrimerization of dipropargylthiazolidinediones with propargyl halides.
Scheme 5: Formation of sultine 13 from compound 8b followed by DA reaction.
Scheme 6: Dipropargylation of 2,4-thiazolidinedione derivatives.
Scheme 7: [2 + 2 + 2] Cycloaddition in the presence of Wilkinson’s catalyst.
Scheme 8: N-Ester derivative 18 hydrolysis to N-acid derivative 22.
Scheme 9: Synthesis of triazolo derivative 24 via click reaction.
Unexpected one-pot formation of the 1H-6a,8a-epiminotricyclopenta[a,c,e][8]annulene system from cyclopentanone, ammonia and dimethyl fumarate. Synthesis of highly strained polycyclic nitroxide and EPR study
- Sergey A. Dobrynin,
- Igor A. Kirilyuk,
- Yuri V. Gatilov,
- Andrey A. Kuzhelev,
- Olesya A. Krumkacheva,
- Matvey V. Fedin,
- Michael K. Bowman and
- Elena G. Bagryanskaya
Beilstein J. Org. Chem. 2019, 15, 2664–2670, doi:10.3762/bjoc.15.259
- carbonyl compounds for the synthesis of heterocyclic compounds has been repeatedly demonstrated [2][3]. We recently used a domino reaction of amino acid, ketone and dimethyl fumarate for the one-pot synthesis of a substituted pyrrolidine, which then was converted into a reduction-resistant pyrrolidine
Graphical Abstract
Scheme 1: Synthesis of compound 1.
Figure 1: X-ray structure of compound 1 (one of the two enantiomers present in the crystal).
Scheme 2: Possible mechanism for the formation of 1.
Figure 2: A possible mechanism for the trans-position of the methyne hydrogens in the azepine ring: the elect...
Figure 3: Selective formation of a single diastereomer in the 1,3-dipolar cycloaddition reaction.
Scheme 3: Synthesis of nitroxide 6.
Figure 4: X-ray structure of compound 6 (one of the two enantiomers present in the crystal).
Scheme 4: A proposed mechanism for nitroxide 6 synthesis.
Figure 5: A, B) Temperature dependence of the electron spin relaxation times in water/glycerol at X-band freq...
Combining the Ugi-azide multicomponent reaction and rhodium(III)-catalyzed annulation for the synthesis of tetrazole-isoquinolone/pyridone hybrids
- Gerardo M. Ojeda,
- Prabhat Ranjan,
- Pavel Fedoseev,
- Lisandra Amable,
- Upendra K. Sharma,
- Daniel G. Rivera and
- Erik V. Van der Eycken
Beilstein J. Org. Chem. 2019, 15, 2447–2457, doi:10.3762/bjoc.15.237
- incorporation of three different diversity-generating sites (Scheme 1A), a feature that has been exploited for the construction of libraries of tetrazole-based compounds with potential bioactivity [9][10][11][12][19]. A powerful approach for obtaining hybrid heterocyclic compounds including the tetrazole ring
Graphical Abstract
Figure 1: Bioactive molecules containing a tetrazole, pyridone or isoquinolone ring.
Scheme 1: Approaches for the synthesis of tetrazoles and isoquinolones and their interplay as designed in thi...
Scheme 2: Scope of the Ugi-azide-4CR/deprotection/acylation sequence. Ugi-azide-4CR conducted at the 2.0 mmol...
Scheme 3: Influence of substituents R and R2 on the reaction outcome. For compounds 4k–m the overall yield in...
Scheme 4: Influence of the alkyne and R1 substituent on the reaction outcome.
Scheme 5: Scope of acrylic, heterocyclic and ring-fused N-acylaminomethyl tetrazole substrates.
Scheme 6: Proposed reaction mechanism using substrates 1a and 3a.
Recent advances in transition-metal-catalyzed incorporation of fluorine-containing groups
- Xiaowei Li,
- Xiaolin Shi,
- Xiangqian Li and
- Dayong Shi
Beilstein J. Org. Chem. 2019, 15, 2213–2270, doi:10.3762/bjoc.15.218
Graphical Abstract
Scheme 1: The main three strategies of fluorination: nucleophilic, electrophilic and radical fluorination.
Scheme 2: Doyle’s Pd-catalyzed fluorination of allylic chlorides.
Scheme 3: Allylic fluorination of 2- and 3-substituted propenyl esters.
Scheme 4: Regioselective allylic fluorination of cinnamyl phosphorothioate esters.
Scheme 5: Palladium-catalyzed aliphatic C–H fluorination reported by Doyle.
Scheme 6: Pd-catalyzed enantioselective fluorination of α-ketoesters followed by stereoselective reduction to...
Scheme 7: Pd-catalyzed C(sp3)–H fluorination of oxindoles.
Scheme 8: C–H fluorination of 8-methylquinoline derivatives with F− reagents.
Scheme 9: Fluorination of α-cyano acetates reported by van Leeuwen.
Scheme 10: The catalytic enantioselective electrophilic C–H fluorination of α-chloro-β-keto phosphonates.
Scheme 11: Fluorination of unactivated C(sp3)–H bonds directed by the bidentate PIP auxiliary.
Scheme 12: Fluorination of C(sp3)–H bonds at the β-position of carboxylic acids.
Scheme 13: Enantioselective benzylic C–H fluorination with a chiral transient directing group.
Scheme 14: Microwave-heated Pd-catalyzed fluorination of aryl alcohols.
Scheme 15: Fluorination of aryl potassium trifluoroborates.
Scheme 16: C(sp2)–F bond formation using precatalyst [L·Pd]2(cod).
Scheme 17: Pd-catalyzed fluorination of (hetero)aryl triflates and bromides.
Scheme 18: The Pd-catalyzed C–H fluorination of arenes with Selectfluor/NFSI.
Scheme 19: Pd(II)-catalyzed ortho-monofluorination protocol for benzoic acids.
Scheme 20: Pd-catalyzed C(sp2)–H bond fluorination of 2-arylbenzothiazoles.
Scheme 21: Nitrate-promoted fluorination of aromatic and olefinic C(sp2)–H bonds and proposed mechanism.
Scheme 22: Fluorination of oxalyl amide-protected benzylamine derivatives.
Scheme 23: C–H fluorination of benzaldehydes with orthanilic acids as transient directing group.
Scheme 24: Pd(II)-catalyzed aryl C–H fluorination with various directing groups.
Scheme 25: Cu-catalyzed aliphatic, allylic, and benzylic fluorination.
Scheme 26: Cu-catalyzed SN2 fluorination of primary and secondary alkyl bromides.
Scheme 27: Copper-catalyzed fluorination of alkyl triflates.
Scheme 28: Cu-catalyzed fluorination of allylic bromides and chlorides.
Scheme 29: Synthetic strategy for the fluorination of active methylene compounds.
Scheme 30: Fluorination of β-ketoesters using a tartrate-derived bidentate bisoxazoline-Cu(II) complex.
Scheme 31: Highly enantioselective fluorination of β-ketoesters and N-Boc-oxindoles.
Scheme 32: Amide group-assisted site-selective fluorination of α-bromocarbonyl compounds.
Scheme 33: Cu-mediated aryl fluorination reported by Sanford [77].
Scheme 34: Mono- or difluorination reactions of benzoic acid derivatives.
Scheme 35: Cu-catalyzed fluorination of diaryliodonium salts with KF.
Scheme 36: Copper(I)-catalyzed cross-coupling of 2-pyridylaryl bromides.
Scheme 37: AgNO3-catalyzed decarboxylative fluorination of aliphatic carboxylic acids.
Scheme 38: The Mn-catalyzed aliphatic and benzylic C–H fluorination.
Scheme 39: Iron(II)-promoted C–H fluorination of benzylic substrates.
Scheme 40: Ag-catalyzed fluorodecarboxylation of carboxylic acids.
Scheme 41: Vanadium-catalyzed C(sp3)–H fluorination.
Scheme 42: AgNO3-catalyzed radical deboronofluorination of alkylboronates and boronic acids.
Scheme 43: Selective heterobenzylic C–H fluorination with Selectfluor reported by Van Humbeck.
Scheme 44: Fe(II)-catalyzed site-selective fluorination guided by an alkoxyl radical.
Scheme 45: Fluorination of allylic trichloroacetimidates reported by Nguyen et al.
Scheme 46: Iridium-catalyzed fluorination of allylic carbonates with TBAF(t-BuOH)4.
Scheme 47: Iridium-catalyzed asymmetric fluorination of allylic trichloroacetimidates.
Scheme 48: Cobalt-catalyzed α-fluorination of β-ketoesters.
Scheme 49: Nickel-catalyzed α-fluorination of various α-chloro-β-ketoesters.
Scheme 50: Ni(II)-catalyzed enantioselective fluorination of oxindoles and β-ketoesters.
Scheme 51: Scandium(III)-catalyzed asymmetric C–H fluorination of unprotected 3-substituted oxindoles.
Scheme 52: Iron-catalyzed directed C–H fluorination.
Scheme 53: Electrophilic silver-catalyzed Ar–F bond-forming reaction from arylstannanes.
Figure 1: Nucleophilic, electrophilic and radical CF3 sources.
Scheme 54: Cu(I)-catalyzed allylic trifluoromethylation of unactivated terminal olefins.
Scheme 55: Direct copper-catalyzed trifluoromethylation of allylsilanes.
Scheme 56: Cupper-catalyzed enantioselective trifluoromethylation of five and six-membered ring β-ketoesters.
Scheme 57: Cu-catalyzed highly stereoselective trifluoromethylation of secondary propargyl sulfonates.
Scheme 58: Remote C(sp3)–H trifluoromethylation of carboxamides and sulfonamides.
Scheme 59: Trifluoromethylation of allylsilanes with photoredox catalysis.
Scheme 60: Ag-catalyzed decarboxylative trifluoromethylation of aliphatic carboxylic acids in aqueous CH3CN.
Scheme 61: Decarboxylative trifluoromethylation of aliphatic carboxylic acids via combined photoredox and copp...
Scheme 62: Palladium-catalyzed Ar–CF3 bond-forming reaction.
Scheme 63: Palladium-catalyzed trifluoromethylation of arenes with diverse heterocyclic directing groups.
Scheme 64: Pd-catalyzed trifluoromethylation of indoles as reported by Liu.
Scheme 65: Pd-catalyzed trifluoromethylation of vinyl triflates and vinyl nonaflates.
Scheme 66: Pd(II)-catalyzed ortho-trifluoromethylation of aromatic C–H bonds.
Scheme 67: Visible-light-induced Pd(OAc)2-catalyzed ortho-trifluoromethylation of acetanilides with CF3SO2Na.
Scheme 68: CuI-catalyzed trifluoromethylation of aryl- and alkenylboronic acids.
Scheme 69: Cu-catalyzed trifluoromethylation of aryl- and vinylboronic acids.
Scheme 70: Copper-catalyzed trifluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 71: Formation of C(sp2)–CF3 bond catalyzed by copper(I) complex.
Scheme 72: Loh’s Cu(I)-catalyzed trifluoromethylation of enamides and electron-deficient alkenes.
Scheme 73: Copper and iron-catalyzed decarboxylative tri- and difluoromethylation.
Scheme 74: Cu-catalyzed trifluoromethylation of hydrazones developed by Bouyssi.
Scheme 75: Cu(I)-catalyzed trifluoromethylation of terminal alkenes.
Scheme 76: Cu/Ag-catalyzed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 77: Copper-catalyzed direct alkenyl C–H trifluoromethylation.
Scheme 78: Copper(I/II)-catalyzed direct trifluoromethylation of styrene derivatives.
Scheme 79: Regioselective trifluoromethylation of pivalamido arenes and heteroarenes.
Scheme 80: Synthesis of trifluoromethylquinones in the presence of copper(I).
Scheme 81: Oxidative trifluoromethylation of imidazoheterocycles in ionic liquid/water.
Scheme 82: A mild and fast continuous-flow trifluoromethylation of coumarins using a CuI/CF3SO2Na/TBHP system.
Scheme 83: Copper-catalyzed oxidative trifluoromethylation of various 8-aminoquinolines.
Scheme 84: PA-directed copper-catalyzed trifluoromethylation of anilines.
Scheme 85: Trifluoromethylation of potassium vinyltrifluoroborates catalyzed by Fe(II).
Scheme 86: Alkenyl trifluoromethylation catalyzed by Ru(phen)3Cl2 as photocatalyst.
Scheme 87: Ru-catalyzed trifluoromethylation of alkenes by Akita’s group.
Scheme 88: Ir-catalyzed Cvinyl–CF3 bond formation of α,β-unsaturated carboxylic acids.
Scheme 89: Ag(I)-catalyzed denitrative trifluoromethylation of β-nitrostyrenes.
Scheme 90: Photocatalyzed direct trifluoromethylation of aryl and heteroaryl C–H bonds.
Scheme 91: Rhenium (MTO)-catalyzed direct trifluoromethylation of aromatic substrates.
Scheme 92: Trifluoromethylation of unprotected anilines under [Ir(ppy)3] catalyst.
Scheme 93: Oxidative trifluoromethylation of imidazopyridines and imidazoheterocycles.
Scheme 94: Ruthenium-catalyzed trifluoromethylation of (hetero)arenes with trifluoroacetic anhydride.
Scheme 95: Phosphovanadomolybdic acid-catalyzed direct C–H trifluoromethylation.
Scheme 96: Picolinamide-assisted ortho-trifluoromethylation of arylamines.
Scheme 97: A nickel-catalyzed C–H trifluoromethylation of free anilines.
Scheme 98: Cu-mediated trifluoromethylation of terminal alkynes reported by Qing.
Scheme 99: Huang’s C(sp)–H trifluoromethylation using Togni’s reagent.
Scheme 100: Cu-catalyzed methods for trifluoromethylation with Umemoto’s reagent.
Scheme 101: The synthesis of alkynyl-CF3 compounds in the presence of fac-[Ir(ppy)3] under visible-light irradi...
Scheme 102: Pd-catalyzed Heck reaction reported by Reutrakul.
Scheme 103: Difluoromethylation of enamides and ene-carbamates.
Scheme 104: Difluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 105: Copper-catalyzed direct C(sp2)–H difluoroacetylation reported by Pannecoucke and co-workers.
Scheme 106: Difluoroalkylation of aldehyde-derived hydrazones with functionalized difluoromethyl bromides.
Scheme 107: Photoredox-catalyzed C–H difluoroalkylation of aldehyde-derived hydrazones.
Scheme 108: Synergistic ruthenium(II)-catalyzed C–H difluoromethylation reported by Ackermann.
Scheme 109: Visible-light photocatalytic decarboxylation of α,β-unsaturated carboxylic acids.
Scheme 110: Synthesis of difluorinated ketones via S-alkyl dithiocarbamates obtained from acyl chlorides and po...
Scheme 111: Synthesis of aryl and heteroaryl difluoromethylated phosphonates.
Scheme 112: Difluoroalkylation of secondary propargyl sulfonates using Cu as the catalyst.
Scheme 113: Ru(II)-mediated para-selective difluoromethylation of anilides and their derivatives.
Scheme 114: Bulky diamine ligand promoted cross-coupling of difluoroalkyl bromides.
Scheme 115: Copper-catalyzed C3–H difluoroacetylation of quinoxalinones.
Scheme 116: Copper(I) chloride-catalyzed trifluoromethylthiolation of enamines, indoles and β-ketoesters.
Scheme 117: Copper-boxmi-catalyzed asymmetric trifluoromethylthiolation of β-ketoesters.
Scheme 118: Direct Cu-catalyzed trifluoromethylthiolation of boronic acids and alkynes.
Scheme 119: Cu-catalyzed synthesis of α-trifluoromethylthio-substituted ketones.
Scheme 120: Trifluoromethylthiolation reactions promoted by diazotriflone and copper.
Scheme 121: Halide activation of N-(trifluoromethylthio)phthalimide.
Scheme 122: The visible light-promoted trifluoromethylthiolation reported by Glorius.
Scheme 123: Synthesis of α-trifluoromethylthioesters via Goossen’s approach.
Scheme 124: Photoinduced trifluoromethylthiolation of diazonium salts.
Scheme 125: Ag-mediated trifluoromethoxylation of aryl stannanes and arylboronic acids.
Scheme 126: Catalytic (hetero)aryl C–H trifluoromethoxylation under visible light.
Scheme 127: Photoinduced C–H-bond trifluromethoxylation of (hetero)arenes.
Friedel–Crafts approach to the one-pot synthesis of methoxy-substituted thioxanthylium salts
- Kenta Tanaka,
- Yuta Tanaka,
- Mami Kishimoto,
- Yujiro Hoshino and
- Kiyoshi Honda
Beilstein J. Org. Chem. 2019, 15, 2105–2112, doi:10.3762/bjoc.15.208
- not been examined. We have developed the synthesis of multisubstituted condensed heterocyclic compounds in the presence of an acid catalyst [15][16][17][18][19][20][21][22][23]. More recently, we have reported the design and synthesis of thioxanthylium organophotoredox catalysts, which can work under
Graphical Abstract
Scheme 1: The representative synthesis of thioxanthylium salts.
Figure 1: The generality of diaryl sulfide 1 and benzoyl chloride 2. aThe reaction was carried out with 1a (2...
Figure 2: The UV–vis spectra of thioxanthylium salt (0.1 mM) in CH3CN.
Figure 3: Frontier orbitals of thioxanthylium salts, calculated by DFT at the B3LYP/6-31G(d,p) level of Orca....
Figure 4: UV–vis spectra of thioxanthylium salts 3b and 4b (0.1 mM) in CH3CN.
Figure 5: Structure of thioxanthylium salt 4.
Figure 6: Cyclic voltammograms of thioxanthylium salts 3b and 4b.
1,2,3,4-Tetrahydro-1,4,5,8-tetraazaanthracene revisited: properties and structural evidence of aromaticity loss
- Arnault Heynderickx,
- Sébastien Nénon,
- Olivier Siri,
- Vladimir Lokshin and
- Vladimir Khodorkovsky
Beilstein J. Org. Chem. 2019, 15, 2059–2068, doi:10.3762/bjoc.15.203
- reviewed, in particular, in three volumes of Chemistry of Heterocyclic Compounds (Editors A. Weisssberger et al.) [1][2][3] and a recent book [4]. During the past years azaacenes attracted interest as potential components of light emitting diodes and electronic devices [5][6][7]. Surprisingly, little is
Graphical Abstract
Figure 1: Quinoxaline derivatives 1–3.
Scheme 1: Synthesis of THTTA (3).
Scheme 2: Protonation, alkylation and acylation of 3.
Figure 2: The ORTEP view of 3. Torsion angles within the benzene ring are given in red.
Figure 3: The ORTEP view of 6a. Torsion angles within the benzene ring are given in red.
Figure 4: The ORTEP view of 7a (the iodine counter anion has been omitted for clarity). Torsion angles within...
Scheme 3: Charge transfer and delocalization within 3 and its diprotonated (6a) and monomethylated (7a) deriv...
Figure 5: Normalized absorption spectra of 3 in: toluene (black), acetone (blue), ethanol (green), water (red...
Figure 6: Protonation of 3 in ethanol. Two isosbestic points (IBP) are indicated by arrows.
Figure 7: Absorption spectra of 7a (blue) and 8 (red) in ethanol.
Figure 8: Absorption spectra of 10a (black), 10b (red). Solid curves: in toluene, dashed curves: in acetone.
Figure 9: View of the supramolecular array generated by 3 in the solid state. Color coding: nitrogen, blue; c...
Figure 10: View of the supramolecular array generated by 6a in the solid state. Color coding: nitrogen, blue; ...
Figure 11: View of the supramolecular array generated by 7a in the solid state. Color coding: nitrogen, blue; ...
Transient and intermediate carbocations in ruthenium tetroxide oxidation of saturated rings
- Manuel Pedrón,
- Laura Legnani,
- Maria-Assunta Chiacchio,
- Pierluigi Caramella,
- Tomás Tejero and
- Pedro Merino
Beilstein J. Org. Chem. 2019, 15, 1552–1562, doi:10.3762/bjoc.15.158
- heterocyclic compounds. Similar differences between the barriers were obtained in acetonitrile (barriers of 16.6, 8.0 and 8.8 kcal/mol for TS1, TS2 and TS3, respectively); the highest observed barriers with respect to water are in agreement with a highly polar reaction. The corresponding transition structure
Graphical Abstract
Scheme 1: Oxidation of alkanes with RuO4.
Scheme 2: Mechanisms for RuO4 oxidation of alkanes.
Scheme 3: Oxidation of saturated five-membered (hetero)cyclic compounds.
Scheme 4: Rate-limiting step for the oxidation of cyclopentane (R1), tetrahydrofuran (R2) and tetrahydrothiop...
Figure 1: Optimized (B3LYP-d3bj/Def2SVP/cpcm=MeCN) geometries of transition structures corresponding to the o...
Figure 2: ELF analysis for the oxidation of cyclopentane (R1). Left: evolution of the electron population alo...
Figure 3: ELF analysis for the oxidation of tetrahydrofuran (R2, A) and tetrahydrothiophene (R3, B). Left: ev...
Figure 4: ELF assignment of electrons to the Ru environment. C(Ru) corresponds to a monosynaptic core basin a...
Scheme 5: Rate-limiting step for the oxidation of N-methyl- and N-benzylpyrrolidines R4 and R5, respectively.
Figure 5: Energy profile for the oxidation of R4 and R5. Relative energies, calculated at the B3LYP-d3bj/Def2...
Figure 6: Optimized (B3LYP-d3bj/Def2SVP/cpcm=water) transition structures for the oxidation of R4 and R5.
Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams
- Edorta Martínez de Marigorta,
- Jesús M. de Los Santos,
- Ana M. Ochoa de Retana,
- Javier Vicario and
- Francisco Palacios
Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104
- preparation of heterocyclic compounds. This is mainly due to the need to find new efficient methods in order to save raw materials and work time. Without doubt, multicomponent approaches in chemical synthesis take the advantage of those two saving features. This economical profit is especially interesting for
Graphical Abstract
Figure 1: γ-Lactam-derived structures considered in this review.
Figure 2: Alkaloids containing an isoindolinone moiety.
Figure 3: Alkaloids containing the 2-oxindole ring system.
Figure 4: Drugs and biological active compounds containing an isoindolinone moiety.
Figure 5: Drugs and biologically active compounds bearing a 2-oxindole skeleton.
Scheme 1: Three-component reaction of benzoic acid 1, amides 2 and DMSO (3).
Scheme 2: Copper-catalysed three-component reaction of 2-iodobenzoic acids 10, alkynylcarboxylic acids 11 and...
Scheme 3: Proposed mechanism for the formation of methylene isoindolinones 13.
Scheme 4: Copper-catalysed three-component reaction of 2-iodobenzamide 17, terminal alkyne 18 and pyrrole or ...
Scheme 5: Palladium-catalysed three-component reaction of ethynylbenzamides 21, secondary amines 22 and CO (23...
Scheme 6: Proposed mechanism for the formation of methyleneisoindolinones 24.
Scheme 7: Copper-catalysed three-component reaction of formyl benzoate 29, amines 2 and alkynes 18.
Scheme 8: Copper-catalysed three-component reaction of formylbenzoate 29, amines 2 and ketones 31.
Scheme 9: Non-catalysed (A) and phase-transfer catalysed (B) three-component reactions of formylbenzoic acids ...
Scheme 10: Proposed mechanism for the formation of isoindolinones 36.
Scheme 11: Three-component reaction of formylbenzoic acid 33, amines 2 and fluorinated silyl ethers 39.
Scheme 12: Three-component Ugi reaction of 2-formylbenzoic acid (33), diamines 41 and isocyanides 42.
Scheme 13: Non-catalysed (A, B) and chiral phosphoric acid promoted (C) three-component Ugi reactions of formy...
Scheme 14: Proposed mechanism for the enantioselective formation of isoindolinones 46.
Scheme 15: Three-component reaction of benzoic acids 33 or 54, amines 2 and TMSCN (52).
Scheme 16: Several variations of the three-component reaction of formylbenzoic acids 33, amines 2 and isatoic ...
Scheme 17: Proposed mechanism for the synthesis of isoindoloquinazolinones 57.
Scheme 18: Three-component reaction of isobenzofuranone 61, amines 2 and isatoic anhydrides 56.
Scheme 19: Palladium-catalysed three-component reaction of 2-aminobenzamides 59, 2-bromobenzaldehydes 62 and C...
Scheme 20: Proposed mechanism for the palladium-catalysed synthesis of isoindoloquinazolinones 57.
Scheme 21: Four-component reaction of 2-vinylbenzoic acids 67, aryldioazonium tetrafluoroborates 68, DABCO·(SO2...
Scheme 22: Plausible mechanism for the formation of isoindolinones 71.
Scheme 23: Three-component reaction of trimethylsilylaryltriflates 77, isocyanides 42 and CO2 (78).
Scheme 24: Plausible mechanism for the three-component synthesis of phthalimides 79.
Scheme 25: Copper-catalysed three-component reaction of 2-formylbenzonitriles 85, arenes 86 and diaryliodonium...
Scheme 26: Copper-catalysed three-component reaction of 2-formylbenzonitriles 85, diaryliodonium salts 87 and ...
Scheme 27: Proposed mechanism for the formation of 2,3-diarylisoindolinones 88, 89 and 92.
Scheme 28: Palladium-catalysed three-component reaction of chloroquinolinecarbaldehydes 97 with isocyanides 42...
Scheme 29: Palladium-catalysed three-component reaction of imines 99 with CO (23) and ortho-iodoarylimines 100....
Scheme 30: Palladium-catalysed three-component reaction of amines 2 with CO (23) and aryl iodide 105.
Scheme 31: Three-component reaction of 2-ethynylanilines 109, perfluoroalkyl iodides 110 and carbon monoxide (...
Scheme 32: Ultraviolet-induced three-component reaction of N-(2-iodoaryl)acrylamides 113, DABCO·(SO2)2 (69) an...
Scheme 33: Proposed mechanism for the preparation of oxindoles 115.
Scheme 34: Three-component reaction of acrylamide 113, CO (23) and 1,4-benzodiazepine 121.
Scheme 35: Multicomponent reaction of sulfonylacrylamides 123, aryldiazonium tetrafluoroborates 68 and DABCO·(...
Scheme 36: Proposed mechanism for the preparation of oxindoles 124.
Scheme 37: Three-component reaction of N-arylpropiolamides 128, aryl iodides 129 and boronic acids 130.
Scheme 38: Proposed mechanism for the formation of diarylmethylene- and diarylallylideneoxindoles 131 and 132.
Scheme 39: Three-component reaction of cyclohexa-1,3-dione (136), amines 2 and alkyl acetylenedicarboxylates 1...
Scheme 40: Proposed mechanism for the formation of 2-oxindoles 138.
Novel (2-amino-4-arylimidazolyl)propanoic acids and pyrrolo[1,2-c]imidazoles via the domino reactions of 2-amino-4-arylimidazoles with carbonyl and methylene active compounds
- Victoria V. Lipson,
- Tetiana L. Pavlovska,
- Nataliya V. Svetlichnaya,
- Anna A. Poryvai,
- Nikolay Yu. Gorobets,
- Erik V. Van der Eycken,
- Irina S. Konovalova,
- Svetlana V. Shiskina,
- Alexander V. Borisov,
- Vladimir I. Musatov and
- Alexander V. Mazepa
Beilstein J. Org. Chem. 2019, 15, 1032–1045, doi:10.3762/bjoc.15.101
- considered as the analogues of both 3,3’-spirooxindole and 2-aminoimidazole marine sponge alkaloids. Keywords: 2-amino-4-arylimidazole; (2-amino-4-arylimidazolyl)propanoic acid; isatin; Meldrum’s acid; multicomponent reactions; pyrrolo[1,2-c]imidazole; 3,3’-spirooxindoles; Introduction Heterocyclic
- compounds of both natural and synthetic origin, containing in their structure pyrrole and imidazole rings, display a wide set of pharmacologically significant activities. The most important natural sources of such systems are marine sponges. Since the 70's of 20th century up to date more than 150
Graphical Abstract
Figure 1: 2-Aminoimidazole alkaloids from marine sponges.
Figure 2: The Knoevenagel–Michael adduct [24] and expected products.
Scheme 1: The three component condensation of imidazo[1,2-a]pyridine, aldehydes and Meldrum’s acid described ...
Figure 3: Molecular structure of 1-([1,1'-biphenyl]-4-yl)-5-oxo-7-phenyl-6,7-dihydro-5H-pyrrolo[1,2-c]imidazo...
Scheme 2: Two forms of cation 9i.
Figure 4: Molecular structure of 3-(2-amino-4-phenyl-1H-imidazol-5-yl)-3-(p-tolyl)propanoic acid 11b accordin...
Scheme 3: Three forms of the compound 11b in the crystal phase.
Scheme 4: Synthesis of the mixture of compounds 13 and 14.
Figure 5: Molecular structure of aminoimidazo[1,2-c]pyrrole 16a according to X-ray diffraction data. Thermal ...
Scheme 5: Resonance structures of 16a.
Figure 6: 3,3’-Spirooxindole alkaloids.
Figure 7: Molecular structure of aminoimidazo[1,2-c]pyrrole 19a according to X-ray diffraction data. Thermal ...
Scheme 6: Resonance structures of 19a.
