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Search for "naphthol" in Full Text gives 84 result(s) in Beilstein Journal of Organic Chemistry.
Construction of cyclic enones via gold-catalyzed oxygen transfer reactions
- Leping Liu,
- Bo Xu and
- Gerald B. Hammond
Beilstein J. Org. Chem. 2011, 7, 606–614, doi:10.3762/bjoc.7.71
- . Surprisingly, acylindene 22 turned out to be the product of this reaction, rather than the expected naphthol (Scheme 16) [52]. However, when a bulky group was substituted on the triple bond, this gold-catalyzed transformation was completely suppressed. Moreover, none of the desired product could be obtained
Graphical Abstract
Scheme 1: Lewis acid or Brønsted acid-catalyzed alkyne–carbonyl metathesis and a proposed [2 + 2] intermediat...
Scheme 2: Gold-catalyzed cyclization of internal alkynyl ketones.
Scheme 3: Proposed [2 + 2] mechanism for the cyclization of alkynyl ketones.
Scheme 4: Gold-catalyzed cyclization of terminal alkynyl ketones.
Scheme 5: Gold-catalyzed tandem oxygen transfer/Nazarov cyclizations.
Scheme 6: TfOH-mediated cyclization of alkynyl ketones.
Scheme 7: Gold-catalyzed cyclizations of 2-alkynyl-1,5-diketones.
Scheme 8: Designed isotopic labeling experiment for mechanistic studies.
Scheme 9: 18O isotopic experiments.
Scheme 10: B2PLYP/6-311+G(d,p)//B2PLYP/6-31G(d) computed reaction profile, relative energies in kcal/mol.
Scheme 11: Gold-catalyzed cyclization of tethered alkynyl arylaldehydes.
Scheme 12: Gold-catalyzed cyclization of terminal diynes.
Scheme 13: Proposed hydrolysis/cyclization mechanism.
Scheme 14: Gold-catalyzed cyclization of internal diynes.
Scheme 15: Proposed solvolysis/cyclization mechanism.
Scheme 16: Gold-catalyzed cyclization of alkynyl epoxides and the 18O isotopic labeling experiment.
Scheme 17: Proposed oxygen transfer mechanism.
Scheme 18: Gold or silver-catalyzed cyclization of alkynyl epoxides and the corresponding deuterium labeling e...
Anion–π interactions influence pKa values
- Christopher J. Cadman and
- Anna K. Croft
Beilstein J. Org. Chem. 2011, 7, 320–328, doi:10.3762/bjoc.7.42
- Christopher J. Cadman Anna K. Croft School of Chemistry, University of Wales Bangor, Bangor, Gwynedd, LL57 2UW, United Kingdom. Fax: +44 1248 370 528. Tel: +44 1248 382 375 10.3762/bjoc.7.42 Abstract Five 8-(4-R-phenyl)-1-naphthol derivatives were prepared by PdCl2-catalysed electrophilic
- of the 1,8-disubstituted naphthalenes 1–5 was carried out following literature procedures [31]. 1-Naphthol (6) was reacted with an 1-iodo-4-R-benzene 7 [R = (a) H, (b) NO2, (c) Cl, (d) Me, (e) OMe] in the presence of a PdCl2 catalyst and Cs2CO3 in DMF at 110 °C for 19–43 h, under Schlenk conditions
- )-1-naphthol derivative 4 was also crystallised and an X-ray crystal structure obtained, confirming the structure (Figure 2). Details are supplied in the Supporting Information Files 4–6. The acid dissociation constants (Ka'), and hence the pKa' values of each of the five derivatives 1–5, were
Graphical Abstract
Figure 1: 1,8-disubstituted naphthalene model systems.
Scheme 1: The general reaction for the preparation of the 1,8-disubstituted naphthol derivatives 1–5 [31].
Figure 2: X-ray structure of 8-(4-methylphenyl)-1-naphthol derivative 4.
Figure 3: Potentiometric titration data for compound 1 and TBAH.
Figure 4: Structures (a) with the hydrogen atom pointing into the ring, as seen in the crystal structure of 4...
Scheme 2: Titration of the acids 1–5 to generate the corresponding anions 8–12, respectively.
Figure 5: Plot of pKa' values for compounds 1–5 versus the corresponding R-substituent σp Hammett parameter. ...
Figure 6: Anion density (HOMO) for the phenyl-derivative 8, illustrating no conjugation of the anion with the...
Figure 7: Bond critical points (red), ring critical points (yellow) and bond paths illustrated for the anion 8...
Surfactant catalyzed convenient and greener synthesis of tetrahydrobenzo[a]xanthene-11-ones at ambient temperature
- Pravin V. Shinde,
- Amol H. Kategaonkar,
- Bapurao B. Shingate and
- Murlidhar S. Shingare
Beilstein J. Org. Chem. 2011, 7, 53–58, doi:10.3762/bjoc.7.9
- our initial study, reaction of 4-chlorobenzaldehyde, β-naphthol and dimedone in water was considered as a standard model reaction (Scheme 1). During this investigation, efforts were mainly focused on a variety of surfactants. In this regard, different cationic surfactants such as
- surfactant was sufficient for catalyzing the reaction effectively. In accordance with the literature [15], a plausible mechanistic path for the formation of tetrahydrobenzo[a]xanthen-11-ones can be outlined as follows: nucleophilic addition of 2-naphthol to the aldehyde to give an intermediate ortho-quinone
- aryl aldehydes were treated with β-naphthol and dimedone under the optimized reaction conditions and all these substrates were found to be equally amenable to these conditions. Interestingly, some heteroaryl aldehydes also underwent the reaction smoothly. Representative results are summarized in Table
Graphical Abstract
Scheme 1: Standard model reaction.
Figure 1: Optical micrograph of the reaction mixture. (A) normal view, (B) magnified view. (Scale bar = 2.5 µ...
Figure 2: Schematic diagram representing the role of TTAB.
β-Hydroxy carbocation intermediates in solvolyses of di- and tetra-hydronaphthalene substrates
- Jaya S. Kudavalli and
- Rory A. More O'Ferrall
Beilstein J. Org. Chem. 2010, 6, 1035–1042, doi:10.3762/bjoc.6.118
- cis and trans isomers, kcis/ktrans = 1800 in aqueous acetonitrile. This mirrors the behaviour of the acid-catalysed dehydration of cis- and trans-naphthalene-1,2-dihydrodiols to form 2-naphthol, for which kcis/ktrans = 440, but contrasts with that for solvolysis of tetrahydronaphthalene substrates, 1
- –H hyperconjugation is particularly pronounced for a β-hydroxynaphthalenium ion intermediate because the stability of its no-bond resonance structure reflects the presence of an aromatic naphthol structure. Keywords: aromaticity; β-hydroxycarbocations; hyperconjugation; solvolysis; Introduction Cis
- case of the more slowly reacting trans isomer there was a competing hydrolysis of the trichloroacetate ester group to give trans-2-methoxy-1,2-dihydro-1-naphthol (6-trans), as shown in Scheme 2. The fraction of hydrolysis was determined by HPLC and was found to increase with increasing water content
Graphical Abstract
Scheme 1: Mechanism of dehydration of benzene-1,2-dihydrodiol.
Figure 1: Reactivity ratios for acid-catalyzed reaction of arene dihydrodiols.
Figure 2: Substrates for solvolysis measurements.
Scheme 2: Products of solvolysis and (ester) hydrolysis of trans-1-trichloroacetoxy-2-methoxy-1,2-dihydronaph...
Scheme 3: Products of solvolysis of trans-1-chloro-2-hydroxy-1,2,3,4-tetrahydronaphthalene.
Figure 3: Rate constants for aqueous solvolyses.
Figure 4: Cis/trans reactivity ratios for β-hydroxycarbocation forming reactions.
Figure 5: Comparison of the effect of a β-hydroxy group on the reactivity of cis and trans di- and tetrahdron...
Scheme 4: ‘Aromatic’ hyperconjugation for the benzenium ion.
Scheme 5: Stereochemistry of carbocation formation from solvolysis of cis-1-trichloroacetoxy-2-hydroxy-1,2-di...
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Studies on polynuclear furoquinones. Part 1: Synthesis of tri- and tetra- cyclic furoquinones simulating BCD/ABCD ring system of furoquinone diterpenoids
- Faruk H. Shaik and
- Gandhi K. Kar
Beilstein J. Org. Chem. 2009, 5, No. 47, doi:10.3762/bjoc.5.47
- the carboxylic acid 16 with TFA and TFAA at room temperature. Finally oxidation of the naphthol derivative 17, with Fremy’s Salt, resulted in the formation of naphtho[1,2-b]furan-4,5-dione (18), as a red solid, in 56% yield. The compounds have been characterized by usual spectroscopic analysis (NMR
Graphical Abstract
Figure 1: Some biologically active tetra cyclic furoquinone derivatives (isolated from Dan Shen) and syntheti...
Figure 2: Key strategies for development of C-ring with quinone functionality.
Figure 3: Retro synthesis of tetra cyclic furoquinone 13.
Scheme 1: Reagents and conditions: i) DDQ (1.5 equiv), dry benzene, reflux, argon atmosphere, 37 h, 83%. ii) ...
Figure 4: Assignment of chemical shifts (1H NMR and 13C NMR) of compound 13.
Scheme 2: Reagents and conditions: i) furan-2-boronic acid (1.2 equiv), Et3N, DMF, Pd(PPh3)4 (2 mol %), 110 °...
Quinoline based receptor in fluorometric discrimination of carboxylic acids
- Kumaresh Ghosh,
- Suman Adhikari,
- Asoke P. Chattopadhyay and
- Purnendu Roy Chowdhury
Beilstein J. Org. Chem. 2008, 4, No. 52, doi:10.3762/bjoc.4.52
- such a manner as to create open clefts of different topologies. Results and Discussion Synthesis The receptors 1 and 2 were synthesised according to Scheme 1. The alcohols 3 and 6, obtained from 8-hydroxyquinoline and 1-naphthol, were coupled with 2-(pivaloylamino)-6-bromomethylpyridine [obtained from
- , 108.7, 73.3, 69.1, 67.8. ESI (positive ionisation): 743.3 (M + Na)+, 721.4 (M + H)+, 361.3, 296.2. FTIR (ν cm−1, KBr) 3385, 1677, 1455, 1318, 1105. 2-(Naphthalen-1-yloxy)ethanol (6) To a mixture of 1-naphthol (1 g, 6.90 mmol) and potassium carbonate (0.96 g, 6.90 mmol) in dry CH3CN, 2-chloroethanol
Graphical Abstract
Figure 1: Structures of compounds 1 and 2.
Scheme 1: Syntheses of receptors 1 and 2.
Figure 2: UV-vis spectra of 1 (c = 5.05 × 10−5 M) in different solvents.
Figure 3: UV-vis spectra of 2 (c = 5.05 × 10−5 M) in different solvents.
Figure 4: UV spectra of the complex of 1 with citric acid (c = 1.67 × 10−5 M) and its change of absorbance on...
Figure 5: UV spectra of the complex of 1 with D-(−)-tartaric acid (c = 1.67 × 10−5 M) and its change of absor...
Figure 6: UV spectra of the complex of 2 with citric acid (c = 1.67 × 10−5 M) and its change of absorbance on...
Figure 7: UV spectra of the complex of 2 with D-(−)-tartaric acid (c = 1.67 × 10−5 M) and its change of absor...
Figure 8: Fluorescence change of 1 in CHCl3 in the presence of carboxylic acids (λex = 290 nm).
Figure 9: Plot of the ratio of excimer to monomer emission vs concentration of the complex of 1 with citric a...
Figure 10: Fluorescence change of 1 in CHCl3 (c = 1.67 × 10−5 M) upon addition of citric acid dissolved in CHCl...
Figure 11: Fluorescence change of 1 in CHCl3 (c = 1.67 × 10−5 M) upon addition of D-(−)-tartaric acid dissolve...
Figure 12: Fluorescence change of 2 in CHCl3 in the presence of carboxylic acids (λex = 290 nm).
Figure 13: Fluorescence change of 2 in CHCl3 (c = 1.67 × 10−5 M) upon addition citric acid dissolved in CHCl3 ...
Figure 14: 1H NMR (in CDCl3) spectra of receptor 1 (c = 3.57 × 10−3 M; bottom) and the 1:1 complex with citric...
Figure 15: AM1 optimized geometries of the complexes of 1 with (a) citric acid, hydrogen bond distances: a = 2...
Figure 16: AM1 optimized geometry of the complex of 2 with citric acid, hydrogen bond distances: a = 2.12 Å, b...
Recent progress on the total synthesis of acetogenins from Annonaceae
- Nianguang Li,
- Zhihao Shi,
- Yuping Tang,
- Jianwei Chen and
- Xiang Li
Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48
Graphical Abstract
Scheme 1: Total synthesis of longifolicin by Marshall’s group.
Scheme 2: Total synthesis of corossoline by Tanaka’s group.
Scheme 3: Total synthesis of corossoline by Wu’s group.
Scheme 4: Total synthesis of pseudo-annonacin A by Hanessian’s group.
Scheme 5: Total synthesis of tonkinecin by Wu’s group.
Scheme 6: Total synthesis of gigantetrocin A by Shi’s group.
Scheme 7: Total synthesis of annonacin by Wu’s group.
Scheme 8: Total synthesis of solamin by Kitahara’s group.
Scheme 9: Total synthesis of solamin by Mioskowski’s group.
Scheme 10: Total synthesis of cis-solamin by Makabe’s group.
Scheme 11: Total synthesis of cis-solamin by Brown’s group.
Scheme 12: The formal synthesis of (+)-cis-solamin by Donohoe’s group.
Scheme 13: Total synthesis of cis-solamin by Stark’s group.
Scheme 14: Total synthesis of mosin B by Tanaka’s group.
Scheme 15: Total synthesis of longicin by Hanessian’s group.
Scheme 16: Total synthesis of murisolin and 16,19-cis-murisolin by Tanaka’s group.
Scheme 17: Synthesis of a stereoisomer library of (+)-murisolin by Curran’s group.
Scheme 18: Total synthesis of murisolin by Makabe’s group.
Scheme 19: Total synthesis of reticulatain-1 by Makabe’s group.
Scheme 20: Total synthesis of muricatetrocin C by Ley’s group.
Scheme 21: Total synthesis of (4R,12S,15S,16S,19R,20R,34S)-muricatetrocin (146) and (4R,12R,15S,16S,19R,20R,34S...
Scheme 22: Total synthesis of parviflorin by Hoye’s group.
Scheme 23: Total synthesis of parviflorin by Trost’s group.
Scheme 24: Total synthesis of trilobacin by Sinha’s group.
Scheme 25: Total synthesis of 15-epi-annonin I 181b by Scharf’s group.
Scheme 26: Total synthesis of squamocin A and squamocin D by Scharf’s group.
Scheme 27: Total synthesis of asiminocin by Marshall’s group.
Scheme 28: Total synthesis of asiminecin by Marshall’s group.
Scheme 29: Total synthesis of (+)-(30S)-bullanin by Marshall’s group.
Scheme 30: Total synthesis of uvaricin by the group of Sinha and Keinan.
Scheme 31: Formal synthesis of uvaricin by Burke’s group.
Scheme 32: Total synthesis of trilobin by Marshall’s group.
Scheme 33: Total synthesis of trilobin by the group of Sinha and Keinan.
Scheme 34: Total synthesis of asimilobin by the group of Wang and Shi.
Scheme 35: Total synthesis of squamotacin by the group of Sinha and Keinan.
Scheme 36: Total synthesis of asimicin by Marshall’s group.
Scheme 37: Total synthesis of asimicin by the group of Sinha and Keinan.
Scheme 38: Total synthesis of asimicin by Roush’s group.
Scheme 39: Total synthesis of asimicin by Marshall’s group.
Scheme 40: Total synthesis of 10-hydroxyasimicin by Ley’s group.
Scheme 41: Total synthesis of asimin by Marshall’s group.
Scheme 42: Total synthesis of bullatacin by the group of Sinha and Keinan.
Scheme 43: Total synthesis of bullatacin by Roush’s group.
Scheme 44: Total synthesis of bullatacin by Pagenkopf’s group.
Scheme 45: Total synthesis of rollidecins C and D by the group of Sinha and Keinan.
Scheme 46: Total synthesis of 30(S)-hydroxybullatacin by Marshall’s group.
Scheme 47: Total synthesis of uvarigrandin A and 5(R)-uvarigrandin A by Marshall’s group.
Scheme 48: Total synthesis of membranacin by Brown’s group.
Scheme 49: Total synthesis of membranacin by Lee’s group.
Scheme 50: Total synthesis of rolliniastatin 1 and rollimembrin by Lee’s group.
Scheme 51: Total synthesis of longimicin D by the group of Maezaki and Tanaka.
Scheme 52: Total synthesis of the structure proposed for mucoxin by Borhan’s group.
Scheme 53: Modular synthesis of adjacent bis-THF annonaceous acetogenins by Marshall’s group.
Scheme 54: Total synthesis of 4-deoxygigantecin by Tanaka’s group.
Scheme 55: Total synthesis of squamostatins D by Marshall’s group.
Scheme 56: Total synthesis of gigantecin by Crimmins’s group.
Scheme 57: Total synthesis of gigantecin by Hoye’s group.
Scheme 58: Total synthesis of cis-sylvaticin by Donohoe’s group.
Scheme 59: Total synthesis of 17(S),18(S)-goniocin by Sinha’s group.
Scheme 60: Total synthesis of goniocin and cyclogoniodenin T by the group of Sinha and Keinan.
Scheme 61: Total synthesis of jimenezin by Takahashi’s group.
Scheme 62: Total synthesis of jimenezin by Lee’s group.
Scheme 63: Total synthesis of jimenezin by Hoffmann’s group.
Scheme 64: Total synthesis of muconin by Jacobsen’s group.
Scheme 65: Total synthesis of (+)-muconin by Kitahara’s group.
Scheme 66: Total synthesis of muconin by Takahashi’s group.
Scheme 67: Total synthesis of muconin by the group of Yoshimitsu and Nagaoka.
Scheme 68: Total synthesis of mucocin by the group of Sinha and Keinan.
Scheme 69: Total synthesis of mucocin by Takahashi’s group.
Scheme 70: Total synthesis of (−)-mucocin by Koert’s group.
Scheme 71: Total synthesis of mucocin by the group of Takahashi and Nakata.
Scheme 72: Total synthesis of mucocin by Evans’s group.
Scheme 73: Total synthesis of mucocin by Mootoo’s group.
Scheme 74: Total synthesis of (−)-mucocin by Crimmins’s group.
Scheme 75: Total synthesis of pyranicin by the group of Takahashi and Nakata.
Scheme 76: Total synthesis of pyranicin by Rein’s group.
Scheme 77: Total synthesis of proposed pyragonicin by the group of Takahashi and Nakata.
Scheme 78: Total synthesis of pyragonicin by Rein’s group.
Scheme 79: Total synthesis of pyragonicin by Takahashi’s group.
Scheme 80: Total synthesis of squamostanal A by Figadère’s group.
Scheme 81: Total synthesis of diepomuricanin by Tanaka’s group.
Scheme 82: Total synthesis of (−)-muricatacin [(R,R)-373a] and its enantiomer (+)-muricatacin [(S,S)-373b] by ...
Scheme 83: Total synthesis of epi-muricatacin (+)-(S,R)-373c and (−)-(R,S)-373d by Scharf’s group.
Scheme 84: Total synthesis of (−)-muricatacin 373a and 5-epi-(−)-muricatacin 373d by Uang’s group.
Scheme 85: Total synthesis of four stereoisomers of muricatacin by Yoon’s group.
Scheme 86: Total synthesis of (+)-muricatacin by Figadère’s group.
Scheme 87: Total synthesis of (+)-epi-muricatacin and (−)-muricatacin by Couladouros’s group.
Scheme 88: Total synthesis of muricatacin by Trost’s group.
Scheme 89: Total synthesis of (−)-(4R,5R)-muricatacin by Heck and Mioskowski’s group.
Scheme 90: Total synthesis of muricatacin (−)-373a by the group of Carda and Marco.
Scheme 91: Total synthesis of (−)- and (+)-muricatacin by Popsavin’s group.
Scheme 92: Total synthesis of (−)-muricatacin by the group of Bernard and Piras.
Scheme 93: Total synthesis of (−)-muricatacin by the group of Yoshimitsu and Nagaoka.
Scheme 94: Total synthesis of (−)-muricatacin by Quinn’s group.
Scheme 95: Total synthesis of montecristin by Brückner’s group.
Scheme 96: Total synthesis of (−)-acaterin by the group of Franck and Figadère.
Scheme 97: Total synthesis of (−)-acaterin by Singh’s group.
Scheme 98: Total synthesis of (−)-acaterin by Kumar’s group.
Scheme 99: Total synthesis of rollicosin by Quinn’s group.
Scheme 100: Total synthesis of Rollicosin by Makabe’s group.
Scheme 101: Total synthesis of squamostolide by Makabe’s group.
Scheme 102: Total synthesis of tonkinelin by Makabe’s group.
Diels- Alder reactions using 4,7-dioxygenated indanones as dienophiles for regioselective construction of oxygenated 2,3-dihydrobenz[f]indenone skeleton
- Natsuno Etomi,
- Takuya Kumamoto,
- Waka Nakanishi and
- Tsutomu Ishikawa
Beilstein J. Org. Chem. 2008, 4, No. 15, doi:10.3762/bjoc.4.15
- ] reported the acid-induced ring opening of 1,4-epoxy-5-methoxynaphthalene (29) to furnish 5-methoxy-1-naphthol (32) via selective C4-O bond cleavage due to the electron-donating effect of the 5-methoxy group (Scheme 4). Therefore, in 5,8-epoxy-2,3-dihydrobenz[f]indenone system 11, regioselective C5-O bond
Graphical Abstract
Figure 1: The structure of kinamycins.
Scheme 1: Retrosynthesis of kinamycins.
Scheme 2: Synthesis of quinones 8 and 12 and the acetals 13 and 14. Reagents and conditions: a) P2O5, CH3SO3H...
Figure 2: Selected HMBC correlations (lines) and NOE enhancements (dash) on 21 (a) and on 22 (b).
Scheme 3: DAR of benzyne 10 and furan (9). Reagents and conditions: a) ethylene glycol, PPTS, benzene, reflux...
Figure 3: Selected HMBC correlations (a) and NOE enhancements (b) on the ring-opened product 27.
Figure 4: Transition states supposed for the regioselective DAR via quinone route.
Figure 5: Representative LUMO coeffients of quinones 8 and 12 (a) and their reaction courses with diene 7 (b)....
Scheme 4: The proposed mechanism for the acid-induced ring opening of epoxynaphthalene 29 by Giles et al. [19].
Scheme 5: Supposed reaction pathways for the acid-induced ring opening of 11.
