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Search for "sodium alkoxide" in Full Text gives 7 result(s) in Beilstein Journal of Organic Chemistry.
Total synthesis of insect sex pheromones: recent improvements based on iron-mediated cross-coupling chemistry
- Eric Gayon,
- Guillaume Lefèvre,
- Olivier Guerret,
- Adrien Tintar and
- Pablo Chourreu
Beilstein J. Org. Chem. 2023, 19, 158–166, doi:10.3762/bjoc.19.15
- described an elegant aryl–aryl cross-coupling procedure suppressing the formation of Grignard homocoupling byproducts relying on the use of FeF3 as catalyst, associated with strong N-heterocyclic carbenes (NHCs) and a source of fluoride anions [28]. A similar procedure involving sodium alkoxide additives
Scheme 1: Structure of the (8E,10Z)-tetradecadienal (1, sex pheromone of the horse-chestnut leaf miner) and r...
Scheme 2: a) Alkyl–vinyl seminal cross-coupling reaction by Kochi; b) improved procedure described by Cahiez.
Scheme 3: Iron-catalyzed cross-coupling of n-OctMgCl with a 1-butadienyl phosphate.
Scheme 4: Synthesis of several insect sex pheromones (a) red bollworm moth, b) European grapevine moth, c) ho...
Scheme 5: Cross-coupling of alkyl Grignard reagents with a) alkenyl or b) aryl halides involving EtOMgCl as a...
Scheme 6: Total synthesis of codling moth sex pheromone 4 using an iron-mediated cross-coupling between an α,...
Synthesis of 2H-furo[2,3-c]pyrazole ring systems through silver(I) ion-mediated ring-closure reaction
- Vaida Milišiūnaitė,
- Rūta Paulavičiūtė,
- Eglė Arbačiauskienė,
- Vytas Martynaitis,
- Wolfgang Holzer and
- Algirdas Šačkus
Beilstein J. Org. Chem. 2019, 15, 679–684, doi:10.3762/bjoc.15.62
- -trisubstituted 2H-furo[2,3-c]pyrazole-5-carboxylic acids and related carboxamides [11][12]. The aforementioned carboxylic acids have been prepared by bromination of the corresponding pyrano[2,3-c]pyrazol-6(1H)-one derivatives followed by heating of the obtained 5-bromo derivatives in the presence of sodium
- alkoxide [11]. Notably, the 2H-furo[2,3-c]pyrazole ring system is structurally similar to the benzo[b]furan system, which is a privileged motif in natural products and biologically active compounds [13][14]. As a result, numerous strategies have been developed for the construction of benzo[b]furan and its
Graphical Abstract
Scheme 1: Preparation of hydroxyalkynyl substrates from 1-phenyl-1H-pyrazol-3-ol (1).
Scheme 2: Cyclization of hydroxyalkynyl substrates to 2,5-disubstituted 2H-furo[2,3-c]pyrazoles.
Figure 1: a) ORTEP diagram of the asymmetric unit consisting of two independent molecules 4d(A) and 4d(B); b)...
An efficient and facile access to highly functionalized pyrrole derivatives
- Meng Gao,
- Wenting Zhao,
- Hongyi Zhao,
- Ziyun Lin,
- Dongfeng Zhang and
- Haihong Huang
Beilstein J. Org. Chem. 2018, 14, 884–890, doi:10.3762/bjoc.14.75
- complete oxidation with DDQ, has been successfully developed. Further transformation with alkylamine/sodium alkoxide alcohol solution conveniently afforded novel polysubstituted pyrroles in good to excellent yields. This methodology for highly functionalized pyrroles performed well over a broad scope of
- cycloaddition of azomethine ylides with N-alkyl maleimide, followed by a facile oxidation using DDQ as oxidant. Further manipulation with alkylamine/sodium alkoxide alcohol solution conveniently led to novel polysubstituted pyrroles in good to excellent yields (Scheme 1). Results and Discussion As shown in
Graphical Abstract
Figure 1: Representative pyrrolo[3,4-c]pyrrole-1,3-diones and polysubstituted pyrrole derivatives.
Scheme 1: Synthetic pathway for the preparation of pyrrolo[3,4-c]pyrrole-1,3-diones and highly substituted py...
Scheme 2: Scope of one-pot synthesis of pyrrolo[3,4-c]pyrrole-1,3-diones 12a–k. General reaction conditions: ...
Scheme 3: Scope of the synthesis of highly substituted pyrrole derivatives 13a–n. General reaction conditions...
Scheme 4: Synthesis of 13k from 12d and ethylamine.
Reactivity studies of pincer bis-protic N-heterocyclic carbene complexes of platinum and palladium under basic conditions
- David C. Marelius,
- Curtis E. Moore,
- Arnold L. Rheingold and
- Douglas B. Grotjahn
Beilstein J. Org. Chem. 2016, 12, 1334–1339, doi:10.3762/bjoc.12.126
- , Figure 2), a situation that would not be possible for a monomeric structure. Attempts to synthesize 5 using sodium alkoxide bases led to the formation of dimer structures 6 with presumed loss of NaCl. Therefore, lithium chloride adducts 7 were targeted because LiCl adduct 3 was isolable yet highly
Graphical Abstract
Figure 1: Previously reported PNHC complexes of interest for this work, along with the targeted complex 5.
Figure 2: Crystal structure of 6-Pd. The atoms of the tert-butyl groups, C–H bonds, and the solvent have been...
Scheme 1: Formation of dimers 6-Pd and 6-Pt by addition of NaOt-Bu.
Scheme 2: Formation of 7 and 8 by addition of LiN(iPr)2 (1 or 2 equiv) (R = tert-butyl).
A convenient four-component one-pot strategy toward the synthesis of pyrazolo[3,4-d]pyrimidines
- Mingxing Liu,
- Jiarong Li,
- Hongxin Chai,
- Kai Zhang,
- Deli Yang,
- Qi Zhang and
- Daxin Shi
Beilstein J. Org. Chem. 2015, 11, 2125–2131, doi:10.3762/bjoc.11.229
- -6-(2-nitrophenyl)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidine was determined by single crystal X-ray diffraction. Keywords: four-component; one-pot; pyrazolo[3,4-d]pyrimidine; sodium alkoxide; Introduction Heterocycles containing a pyrimidine ring are extensively present in natural products and are very
- could promote the reaction to produce 5a, though DBU needed a higher reaction temperature (Table 1, entries 4–6). Taking into account the yield of the reaction, sodium alkoxide was the best choice. The reaction performed in alcohol resulted in the highest yield (Table 1, entries 6–9). The reaction
- temperature was screened and the appropriate temperature was found to be 60 °C (Table 1, entries 6, 10 and 11). The amount of catalyst had an effect on the reaction and 1.2 equivalents of sodium alkoxide was the most appropriate choice (Table 1, entries 12 and 13). This means that sodium alkoxide is not only
Graphical Abstract
Scheme 1: The synthesis of pyrazolo[3,4-d]pyrimidines.
Figure 1: Four-component one-pot synthesis of 5. Reactions conditions: 1 (1.2 mmol), 2 (1.0 mmol), 3 (1.2 mmo...
Scheme 2: Synthesis of 5a from different intermediates.
Scheme 3: Possible reaction mechanisms for the formation of pyrazolo[3,4-d]pyrimidiine.
Figure 2: Molecular structure (from X-ray diffraction data) of 5g.
An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles
- Marcus Baumann and
- Ian R. Baxendale
Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265
- 1.80 is then hydrolysed to reveal once again the amino acid functionality, which upon diazotisation in the presence of hydrobromic acid selectively forms the α-bromo ester 1.82. A more direct SNAr approach utilising 4-fluorobenzonitrile as the acceptor and the sodium alkoxide of hydroxyethylpyridine
Graphical Abstract
Scheme 1: Scaled industrial processes for the synthesis of simple pyridines.
Scheme 2: Synthesis of nicotinic acid from 2-methyl-5-ethylpyridine (1.11).
Scheme 3: Synthesis of 3-picoline and nicotinic acid.
Scheme 4: Synthesis of 3-picoline from 2-methylglutarodinitrile 1.19.
Scheme 5: Picoline-based synthesis of clarinex (no yields reported).
Scheme 6: Mode of action of proton-pump inhibitors and structures of the API’s.
Scheme 7: Hantzsch-like route towards the pyridine rings in common proton pump inhibitors.
Figure 1: Structures of rosiglitazone (1.40) and pioglitazone (1.41).
Scheme 8: Synthesis of rosiglitazone.
Scheme 9: Syntheses of 2-pyridones.
Scheme 10: Synthesis and mechanism of 2-pyrone from malic acid.
Scheme 11: Polymer-assisted synthesis of rosiglitazone.
Scheme 12: Synthesis of pioglitazone.
Scheme 13: Meerwein arylation reaction towards pioglitazone.
Scheme 14: Route towards pioglitazone utilising tyrosine.
Scheme 15: Route towards pioglitazone via Darzens ester formation.
Scheme 16: Syntheses of the thiazolidinedione moiety.
Scheme 17: Synthesis of etoricoxib utilising Negishi and Stille cross-coupling reactions.
Scheme 18: Synthesis of etoricoxib via vinamidinium condensation.
Figure 2: Structures of nalidixic acid, levofloxacin and moxifloxacin.
Scheme 19: Synthesis of moxifloxacin.
Scheme 20: Synthesis of (S,S)-2,8-diazabicyclo[4.3.0]nonane 1.105.
Scheme 21: Synthesis of levofloxacin.
Scheme 22: Alternative approach to the levofloxacin core 1.125.
Figure 3: Structures of nifedipine, amlodipine and clevidipine.
Scheme 23: Mg3N2-mediated synthesis of nifedipine.
Scheme 24: Synthesis of rac-amlodipine as besylate salt.
Scheme 25: Aza Diels–Alder approach towards amlodipine.
Scheme 26: Routes towards clevidipine.
Figure 4: Examples of piperidine containing drugs.
Figure 5: Discovery of tiagabine based on early leads.
Scheme 27: Synthetic sequences to tiagabine.
Figure 6: Structures of solifenacin (2.57) and muscarine (2.58).
Scheme 28: Enantioselective synthesis of solifenacin.
Figure 7: Structures of DPP-4 inhibitors of the gliptin-type.
Scheme 29: Formation of inactive diketopiperazines from cis-rotameric precursors.
Figure 8: Co-crystal structure of carmegliptin bound in the human DPP-4 active site (PDB 3kwf).
Scheme 30: Improved route to carmegliptin.
Figure 9: Structures of lamivudine and zidovudine.
Scheme 31: Typical routes accessing uracil, thymine and cytosine.
Scheme 32: Coupling between pyrimidones and riboses via the Vorbrüggen nucleosidation.
Scheme 33: Synthesis of lamivudine.
Scheme 34: Synthesis of raltegravir.
Scheme 35: Mechanistic studies on the formation of 3.22.
Figure 10: Structures of selected pyrimidine containing drugs.
Scheme 36: General preparation of pyrimidines and dihydropyrimidones.
Scheme 37: Synthesis of imatinib.
Scheme 38: Flow synthesis of imatinib.
Scheme 39: Syntheses of erlotinib.
Scheme 40: Synthesis of erlotinib proceeding via Dimroth rearrangement.
Scheme 41: Synthesis of lapatinib.
Scheme 42: Synthesis of rosuvastatin.
Scheme 43: Alternative preparation of the key aldehyde towards rosuvastatin.
Figure 11: Structure comparison between nicotinic acetylcholine receptor agonists.
Scheme 44: Syntheses of varenicline and its key building block 4.5.
Scheme 45: Synthetic access to eszopiclone and brimonidine via quinoxaline intermediates.
Figure 12: Bortezomib bound in an active site of the yeast 20S proteasome ([114], pdb 2F16).
Scheme 46: Asymmetric synthesis of bortezomib.
Figure 13: Structures of some prominent piperazine containing drugs.
Figure 14: Structural comparison between the core of aplaviroc (4.35) and a type-1 β-turn (4.36).
Scheme 47: Examplary synthesis of an aplaviroc analogue via the Ugi-MCR.
Scheme 48: Syntheses of azelastine (5.1).
Figure 15: Structures of captopril, enalapril and cilazapril.
Scheme 49: Synthesis of cilazapril.
Figure 16: Structures of lamotrigine, ceftriaxone and azapropazone.
Scheme 50: Synthesis of lamotrigine.
Scheme 51: Alternative synthesis of lamotrigine (no yields reported).
Figure 17: Structural comparison between imiquimod and the related adenosine nucleoside.
Scheme 52: Conventional synthesis of imiquimod (no yields reported).
Scheme 53: Synthesis of imiquimod.
Scheme 54: Synthesis of imiquimod via tetrazole formation (not all yields reported).
Figure 18: Structures of various anti HIV-medications.
Scheme 55: Synthesis of abacavir.
Figure 19: Structures of diazepam compared to modern replacements.
Scheme 56: Synthesis of ocinaplon.
Scheme 57: Access to zaleplon and indiplon.
Scheme 58: Different routes towards the required N-methylpyrazole 6.65 of sildenafil.
Scheme 59: Polymer-supported reagents in the synthesis of key aminopyrazole 6.72.
Scheme 60: Early synthetic route to sildenafil.
Scheme 61: Convergent preparations of sildenafil.
Figure 20: Comparison of the structures of sildenafil, tadalafil and vardenafil.
Scheme 62: Short route to imidazotriazinones.
Scheme 63: Alternative route towards vardenafils core imidazotriazinone (6.95).
Scheme 64: Bayer’s approach to the vardenafil core.
Scheme 65: Large scale synthesis of vardenafil.
Scheme 66: Mode of action of temozolomide (6.105) as methylating agent.
Scheme 67: Different routes to temozolomide.
Scheme 68: Safer route towards temozolomide.
Figure 21: Some unreported heterocyclic scaffolds in top market drugs.
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.
