Synthesis of α-(4-Oxazolyl)amino Esters via Brønsted Acid Catalyzed Tandem Reaction
作者:Ansoo Lee、Seohee Oh、Hyunwoo Kim
DOI:10.1021/acs.orglett.8b01212
日期:2018.6.1
A one-step, Brønsted acid catalyzed tandem reaction for the synthesis of α-(4-oxazolyl)amino esters was developed. 4-Nitrobenzenesulfonic acid was found to be an efficient catalyst for the coupling of ethyl 2-oxobut-3-ynoates with amides to provide various α-(4-oxazolyl)amino esters. The experimental and X-ray crystallographic data suggest that a series of bond-forming reactions including imine formation
Niobium Pentachloride Promoted Conversion of Carboxylic Acids to Carboxamides: Synthesis of the 4-Aryl-1,2,3,4-tetrahydroisoquinoline Alkaloid Structures
作者:Claudio C. Lopes、Rosangela S. Lopes、Marcelo S. Nery、Renata P. Ribeiro
DOI:10.1055/s-2003-36823
日期:——
A practical method for the conversion of carboxylic acids to the corresponding carboxamides mediated by niobium pentachloride under mild conditions is described. The synthesis of the 4-aryl-1,2,3,4-tetrahydroisoquinoline alkaloid structures was accomplished via benzylic lithiation of N-methyl-3,4-dimethoxy-2-(4'-methoxybenzyl)benzamide.
Rh<sup>III</sup>‐Catalyzed Oxidative Olefination of Vinylic CH Bonds: Efficient and Selective Access to Di‐unsaturated α‐Amino Acid Derivatives and Other Linear 1,3‐Butadienes
作者:Tatiana Besset、Nadine Kuhl、Frederic W. Patureau、Frank Glorius
DOI:10.1002/chem.201101340
日期:2011.6.20
get‐together! A RhIII‐catalyzedoxidative cross‐coupling of different olefins was developed, resulting in the formation of valuable linear butadiene products and especially di‐unsaturated α‐amino acid derivatives. 1,1‐Di‐, 1,2‐di‐, and 1,1,2‐trisubstituted olefins could be coupled with styrenes and acrylates. In these reactions, remarkably high levels of chemo‐, regio‐, and stereoselectivity were obtained
Convenient Synthesis of Various Substituted Homotaurines from Alk-2-enamides
作者:Youfeng Nai、Jiaxi Xu
DOI:10.1002/hlca.201200547
日期:2013.7
Various substituted homotaurines (=3‐aminopropane‐1‐sulfonic acids) 6 were readily synthesized in satisfactory to good yields via the Michael addition of thioacetic acid to alk‐2‐enamides 3 (→4), followed by LiAlH4 reduction (→5) and performic acid oxidation (Scheme 1). The configuration of ‘anti’‐disubstituted homotaurine ‘anti’‐6h was deduced from the 3‐(acetylthio)alkanamide (=S‐(3‐amino‐1,2‐dimethyl‐3‐oxopropyl)
Enzymatic nitrile hydrolysis catalyzed by nitrilase ZmNIT2 from maize. An unprecedented β-hydroxy functionality enhanced amide formation
作者:Chandrani Mukherjee、Dunming Zhu、Edward R. Biehl、Rajiv R. Parmar、Ling Hua
DOI:10.1016/j.tet.2006.04.069
日期:2006.6
To explore the synthetic potential of nitrilase ZmNIT2 from maize, the substrate specificity of this nitrilase was studied with a diverse collection of nitriles. The nitrilase ZmNIT2 showed high activity for all the tested nitriles except benzonitrile, producing both acids and amides. For the hydrolysis of aliphatic, aromatic nitriles, phenylacetonitrile derivatives and dinitriles, carboxylic acids