CONCISE BETA2-AMINO ACID SYNTHESIS VIA ORGANOCATALYTIC AMINOMETHYLATION
申请人:CHI Yonggui
公开号:US20080058548A1
公开(公告)日:2008-03-06
The present invention provides a method for the synthesis of β
2
-amino acids. The method also provides methods yielding α-substituted β-amino aldehydes and β-substituted γ-amino alcohols. The present method according to this invention allows for increased yield and easier purification using minimal chromatography or crystallization. The methods described herein are based on an aldehyde aminomethylation which involves a Mannich reaction between an aldehyde and a formaldehyde-derived N,O-acetal (iminium precursor) and a catalyst, such as, for example, L-proline or a pyrrolidine. The invention allows for large scale, commercial preparation of β
2
-amino acids.
Asymmetric Carbon−Carbon Bond Formation γ to a Carbonyl Group: Phosphine-Catalyzed Addition of Nitromethane to Allenes
作者:Sean W. Smith、Gregory C. Fu
DOI:10.1021/ja9061823
日期:2009.10.14
A chiral phosphine catalyzes the addition of a carbon nucleophile to the gamma position of an etectron-poor allene (amide-, ester-, or phosphonate-substituted), in preference to isomerization to a 1,3-diene, in good ee and yield. This strategy provides an attractive method for the catalytic asymmetric gamma functionalization of carbonyl (and related) compounds.
WO2007/112358
申请人:——
公开号:——
公开(公告)日:——
US7820858B2
申请人:——
公开号:US7820858B2
公开(公告)日:2010-10-26
Enantioselective Organocatalytic Aminomethylation of Aldehydes: A Role for Ionic Interactions and Efficient Access to β<sup>2</sup>-Amino Acids
作者:Yonggui Chi、Samuel H. Gellman
DOI:10.1021/ja061731n
日期:2006.5.1
Organocatalytic Mannich addition of aldehydes to a formaldehyde-derived iminium species catalyzed by proline-derived chiral pyrrolidines provides beta-amino aldehydes with >/=90% ee. Mechanistic analysis of the proline-catalyzed reactions suggests that non-hydrogen-bonded ionic interactions at the Mannich reaction transition state can influence stereochemical outcome. The beta-amino aldehydes from our process bear a substituent adjacent to the carbonyl and can be efficiently converted to protected beta2-amino acids, which are important building blocks for beta-peptide foldamers that display useful biological activities.