33831-72-0Relevant academic research and scientific papers
Carbene-Catalyzed [4 + 2] Annulation of 2 H-Azirine-2-carboxaldehydes with Ketones via Azolium Aza-Dienolate Intermediate
Peng, Qiupeng,Zhang, Bei,Xie, Yangxi,Wang, Jian
, p. 7641 - 7644 (2018)
A new carbene-catalyzed [4 + 2] annulation of 2H-azirine-2-carbaldehydes with ketones was developed, thus providing the 2,3-dihydro-6H-1,3-oxazin-6-one core structures with broad scope and good to excellent yields. Notably, the azolium aza-dienolates gene
Green synthesis method of nicotinic acid ester compounds based on non-metallic conditions
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Paragraph 0052; 0055, (2021/09/29)
The invention discloses a green synthesis method based on nicotinic acid ester compounds under non-metallic conditions, and belongs to the technical field of organic synthesis. The method comprises the following steps of (III) replacing cyclopropanol and (II) substituted enamine ester as a raw material, taking tetramethyl piperidine nitrogen oxide as an oxidizing agent, 110 - 130 °C, stirring and reacting in an organic solvent to synthesize a (I) nicotinate compound. The invention provides a green synthesis method based on nicotinic acid ester compounds under non-metallic conditions, wherein cyclopropanols and enamine esters are taken as raw materials, and a polysubstituted nicotinate is synthesized through a strategy of oxidative dehydrogenation of ketene cyclization.
Electrochemical Oxidative Cyclization: Synthesis of Polysubstituted Pyrrole from Enamines
Chen, Zhiwei,Shi, Guang,Tang, Wei,Sun, Jie,Wang, Wenxing
supporting information, p. 951 - 955 (2021/02/03)
A conceptually novel method for the preparation of pyrrole is described by electrochemical-oxidation-induced intermolecular annulation via enamines. In a simple undivided cell, based on a sodium acetate-facilitated, polysubstituted pyrrole derivations has been facilely synthesized under external oxidant-free condition. This electrosynthetic approach providing an environmentally benign protocol for C?C bond cross-coupling and oxidative annulation, which features unparalleled broad scope of substrates and practicality.
Cu-Mediated Expeditious Annulation of Alkyl 3-Aminoacrylates with Aryldiazonium Salts: Access to Alkyl N2-Aryl 1,2,3-Triazole-carboxylates for Druglike Molecular Synthesis
Liu, Hao-Nan,Cao, Hao-Qiang,Cheung, Chi Wai,Ma, Jun-An
, p. 1396 - 1401 (2020/02/22)
Alkyl N-aryl 1,2,3-triazole-carboxylates are important molecules or intermediates in medicinal chemistry, but the synthesis of N2-aryl counterparts remains elusive. Herein, we describe a Cu-mediated annulation reaction of alkyl 3-aminoacrylates with aryldiazonium salts, both of which are readily available substrates. Furthermore, alkyl 2-aminoacrylates are also viable substrates. Diverse alkyl N2-aryl 1,2,3-triazole-carboxylates and their analogues can be rapidly prepared under mild conditions. Especially, this protocol allows one to access several druglike variants of carbonic anhydrase inhibitors and celecoxib.
Divergent Synthesis of Multisubstituted Unsymmetric Pyrroles and Pyrrolin-4-ones from Enamino Esters via Copper-Catalyzed Aerobic Dimerization
Chen, Zhi-Wei,Zheng, Lei,Liu, Jin
, p. 3051 - 3060 (2019/05/24)
A facile synthetic method to access multisubstituted unsymmetric pyrrole and pyrrolin-4-one derivatives is disclosed. In the presence of Cu(OAc)2 and KOAc, substituted pyrrole derivatives are produced in good yields (up to 93 %) through oxidative cyclization of enamino esters. Meanwhile, using CuCl2 and TFA (trifluoroacetic acid), pyrrolin-4-one derivatives are obtained in excellent yields (up to 94 %) through 1,2-aryl migration. A wide range of functional groups have been tolerated, and a reliable method for the synthesis of valuable multisubstituted pyrroles and pyrrolin-4-ones has been developed.
Copper-Catalyzed Tandem Reaction of Enamino Esters with ortho-Halogenated Aromatic Carbonyls: One-Pot Approach to Functionalized Quinolines
Peng, Fei,Liu, Jin,Li, Lili,Chen, Zhiwei
supporting information, p. 666 - 672 (2018/02/14)
An efficient and practical approach for the synthesis of functionalized quinolines has been developed by using the copper-catalyzed tandem C–C bond formation and C–N coupling reaction of enamino esters and ortho-halogenated aromatic carbonyl compounds. Various functional groups were tolerated under the reaction conditions, and a series of quinolines were easily obtained in moderate to good yields. A gram-scale reaction was also performed to demonstrate a further application of this synthetic method.
Nickel-catalyzed enantioselective hydrogenation of β-(acylamino)acrylates: Synthesis of chiral β-amino acid derivatives
Li, Xiuxiu,You, Cai,Li, Shuailong,Lv, Hui,Zhang, Xumu
, p. 5130 - 5133 (2017/11/06)
The nickel-catalyzed asymmetric hydrogenation of β-(acylamino)acrylates has been developed, affording chiral β-amino acid derivatives with excellent yields (95-99% yield) and enantioselectivities (97-99% ee). With the Ni-Binapine system, high enantioselectivities (98-99% ee) have also been obtained in the hydrogenation of Z/E isomeric mixtures of β-alkyl and β-aryl β-(acylamino)acrylates. The synthesis of chiral β-amino acid derivatives on a gram scale has also been achieved with 0.2 mol % catalyst loading.
Rhodium-catalyzed enantioseletive hydrogenation of tetrasubstituted α-acetoxy β-enamido esters: A new approach to chiral α-hydroxyl-β-amino acid derivatives
Wang, Qingli,Huang, Wenhua,Yuan, Haoquan,Cai, Qin,Chen, Liming,Lv, Hui,Zhang, Xumu
, p. 16120 - 16123 (2015/02/18)
Asymmetric hydrogenation of tetrasubtitued α-acetoxy β-enamido esters with rhodium catalysts based on chiral diphosphine ligands provides an efficient and concise route to the synthesis of chiral α-hydroxyl-β-amino acid derivatives in excellent enantioselectivities. The products are valuable chiral building blocks in many biologically active compounds and have important applications in organic synthesis.
C1-symmetric bisphosphine ligands and their use in the asymmetric synthesis of pregabalin
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Page/Page column 22, (2008/06/13)
Materials and methods for preparing (S)-(+)-3-(aminomethyl)-5-methyl-hexanoic acid and structurally related compounds via enantioselective hydrogenation of prochiral olefins are disclosed. The methods employ novel chiral catalysts, which include C1-symmetric bisphosphine ligands bound to transition metals.
PYRIDINE COMPOUNDS AS INHIBITORS OF DIPEPTIDYL PEPTIDASE IV
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Page/Page column 132, (2010/02/11)
A compound represented by the formula wherein R1 and R2 are the same or different and each is an optionally substituted hydrocarbon group or an optionally substituted hydroxy group; R3 is an optionally substituted aromatic group; R4 is an optionally substituted amino group; L is a divalent chain hydrocarbon group; Q is a bond or a divalent chain hydrocarbon group; and X is a hydrogen atom, a cyano group, a nitro group, an acyl group, a substituted hydroxy group, an optionally substituted thiol group, an optionally substituted amino group or an optionally substituted cyclic group; provided that when X is an ethoxycarbonyl group, then Q is a divalent chain hydrocarbon group. The compound has a peptidase inhibitory action, is useful as an agent for the prophylaxis or treatment of diabetes and the like, and is superior in efficacy, duration of action, specificity, lower toxicity and the like.
