[EN] ASYMMETRIC MICHAEL AND ALDOL ADDITION USING BIFUNCTIONAL CINCHONA-ALKALOID-BASED CATALYSTS<br/>[FR] ADDITIONS ASYMETRIQUES DE MICHAEL ET D'ALDOL UTILISANT DES CATALYSEURS BIFONCTIONNELS A BASE DE CINCHONINE
申请人:UNIV BRANDEIS
公开号:WO2005121137A1
公开(公告)日:2005-12-22
One aspect of the present invention relates to quinine-based and quinidine-based catalysts. Another aspect of the invention relates to a method of preparing a derivatized quinine-based or quinidine-based catalyst comprising 1) reacting quinine or quinidine with 5 base and a compound that has a suitable leaving group, and 2) converting the ring methoxy group to a hydroxy group. Another aspect of the present invention relates to a method of preparing a chiral, non-racemic compound from a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral ketone, comprising the step of: reacting a prochiral electron-deficient alkene or azo compound or prochiral aldehyde or prochiral 10 ketone with a nucleophile in the presence of a catalyst; thereby producing a chiral, non racemic compound; wherein said catalyst is a derivatized quinine or quinidine. Another aspect of the present invention relates to a method of kinetic resolution, comprising the step of reacting racemic chiral alkene with a nucleophile in the presence of a derivatized quinine or quinidine.
Supported and Unsupported Chiral Squaramides as Organocatalysts for Stereoselective Michael Additions: Synthesis of Enantiopure Chromenes and Spirochromanes
作者:José M. Andrés、Jorge Losada、Alicia Maestro、Patricia Rodríguez-Ferrer、Rafael Pedrosa
DOI:10.1021/acs.joc.7b01177
日期:2017.8.18
Novel supported chiral bifunctional squaramides have been easily prepared starting from diamines derivedfrom natural amino acids and commercially available aminoalkyl polystyrene resins. These squaramides behave as excellent stereoselective recoverable organocatalysts in different Michael additions, in neat conditions at room temperature. The reaction on 2-(2-nitrovinyl) phenol as electrophile lead
motifs in organocatalysis, whereas efficient 1,3‐diamine‐derived organocatalysts are very rare. Herein we report a highly efficient camphor‐1,3‐diamine‐derived squaramideorganocatalyst. Its catalytic activity in Michaeladditions of 1,3‐dicarbonyl nucleophiles to trans‐β‐nitrostyrene derivatives provides excellent enantioselectivities (up to >99% ee).
Recyclable Chiral Bifunctional Thioureas Derived from [60]Fullerene and Their Use as Highly Efficient Organocatalysts for the Asymmetric Nitro-Michael Reaction
作者:José M. Andrés、Miguel González、Alicia Maestro、Daniel Naharro、Rafael Pedrosa
DOI:10.1002/ejoc.201601640
日期:2017.5.18
Three novel fullerothioureas derived from natural valine, phenylalanine, and tert-leucine have been prepared by Prato's reaction of [60]fullerene and the corresponding aldehydes. These hybrids have been used as organocatalysts in a typical stereoselective nitro-Michael addition reaction under homogeneous and neat conditions. The catalysts are easily recoverable by filtration, and are recyclable for
thiourea-modified l-Leu-based peptide (3,5-diCF3Ph)NHC(=S)-(l-Leu-l-Leu-Ac5c)2-OMe} with five-membered ring α,α-disubstituted α-amino acids (Ac5c) catalyzed a highly enantioselective 1,4-addition reaction between β-nitrostyrene and dimethyl malonate. The enantioselective reaction required only 0.5 mol % chiral peptide-catalyst in the presence of iPr2EtN (2.5 equiv.), and gave a 1,4-adduct with 93 % ee of
N-末端硫脲修饰的基于l -Leu 的肽 (3,5-diCF 3 Ph)NHC(=S)-( l -Leu- l -Leu-Ac 5 c) 2 -OMe} 具有五元环α,α-二取代的α-氨基酸(Ac 5 c)催化了β-硝基苯乙烯和丙二酸二甲酯之间的高度对映选择性1,4-加成反应。在i Pr 2 EtN(2.5 当量)存在下,对映选择性反应仅需要 0.5 mol% 的手性肽催化剂,并得到 1,4-加合物,93% ee,产率为 85%。作为迈克尔受体,各种β-硝基苯乙烯衍生物,如甲基、对氟、对溴和对可以应用苯基上的-甲氧基取代基、2-呋喃基、2-噻吩基和萘基β-硝基乙烯。此外,各种丙二酸烷基酯和环状β-酮酯可用作迈克尔供体。很明显,肽链的长度、右手螺旋结构、酰胺 N-Hs 和 N 端硫脲部分在不对称诱导中起着至关重要的作用。