A Multistage, One-Pot Procedure Mediated by a Single Catalyst: A New Approach to the Catalytic Asymmetric Synthesis of β-Amino Acids
作者:Ahmed M. Hafez、Travis Dudding、Ty R. Wagerle、Meha H. Shah、Andrew E. Taggi、Thomas Lectka
DOI:10.1021/jo034150e
日期:2003.7.1
A catalytic asymmetric procedure for the preparation of beta-amino acids (specifically beta-substituted aspartic acid derivatives) is reported. The cinchona alkaloid catalyst benzoylquinine (BQ) mediates up to five distinct steps of a reaction pathway, all in one reaction vessel. The products of this reaction, highly optically enriched beta-substituted aspartic acid derivatives, were prepared from
Synthesis of 5-Amino-oxazole-4-carboxylates from α-Chloroglycinates
作者:Jianmin Zhang、Pierre-Yves Coqueron、Jean-Pierre Vors、Marco A. Ciufolini
DOI:10.1021/ol101704r
日期:2010.9.3
Aluminum-based Lewis acids are effective promoters of the condensation of alpha-chloroglycinates with isonitriles or with cyanide ion, leading to the formation of 5-amino-oxazoles.
Iterative Oxazole Assembly via α-Chloroglycinates: Total Synthesis of (−)-Muscoride A
作者:Pierre-Yves Coqueron、Charles Didier、Marco A. Ciufolini
DOI:10.1002/anie.200390363
日期:2003.3.28
A direct route to 2-alkyl-4-carbethoxy-5-vinyloxazoles
作者:Jianmin Zhang、Marco A. Ciufolini
DOI:10.1016/j.tetlet.2010.06.130
日期:2010.9
The reaction of an alpha-chloroglycinate ester with the dimethylaluminum acetylide derivative of phenyl propargyl ether provides the corresponding 5-vinyloxazole in 40-50% yield. (C) 2010 Elsevier Ltd. All rights reserved.
Asymmetric Catalysis on Sequentially-Linked Columns
作者:Ahmed M. Hafez、Andrew E. Taggi、Travis Dudding、Thomas Lectka
DOI:10.1021/ja016556j
日期:2001.11.1
We report a catalytic asymmetric reaction process that involves the use of solid-phase reagents and catalysts that constitute the packing of a series of "reaction columns". This process was applied to the catalytic asymmetric synthesis of beta -lactams, to yield pure products with excellent enantio- and diastereoselectivity. We have identified several advantages to conducting chemical reactions on sequential columns, including ease of catalyst and reagent recovery and simplified purification steps that preclude the need for chromatography.