Diastereoselective nucleophilic additions to imines attached to tricarbonyl(arene)chromium moieties
作者:Dorothy M. David、Leon A. P. Kane-Maguire、Stephen G. Pyne
DOI:10.1039/dt9940000289
日期:——
A range of imine complexes has been prepared which possess planar chirality associated with the attached tricarbonyl(1,2-disubstituted arene)chromium moiety. Nucleophilic addition to the imine group of these complexes occurs with high diastereoselectivity, providing an efficient route to the asymmetric synthesis of chiral amines. The stereochemical outcome of the additions may be rationalized in terms
Process for producing 4,4,4,- trifluoro-3-hydroxybutyric acid
申请人:CENTRAL GLASS COMPANY, LIMITED
公开号:US20030088095A1
公开(公告)日:2003-05-08
A first process for producing an optically active perfluoroalkylcarbinol derivative includes (a) reacting an optically active imine with a compound that is a hemiacetal of a perfluoroalkylaldehyde or a hydrate of a perfluoroalkylaldehyde to obtain a condensate; and (b) hydrolyzing the condensate under an acid condition. A second process for increasing optical purity of an optically active 4,4,4-trifluoro 3-hydroxy-1-aryl-1-butanone derivative includes (a) precipitating a racemic crystal of the derivative, from the derivative; and (b) removing the racemic crystal from the derivative. A third process for increasing optical purity of the butanone derivative includes recrystallizing the derivative. Novel compounds are optically active and inactive 4,4,4-trifluoro-3-hydroxybutanoic aryl ester derivatives. A fourth process for producing an optically active or optically inactive 4,4,4-trifluoro-3-hydroxybutyric acid aryl ester derivative includes oxidizing an optically active or optically inactive 4,4,4-trifluoro-3-hydroxy-1-aryl-1-butanone derivative. A fifth process for increasing optical purity of the optically active aryl ester derivative includes recrystallizing the derivative. A sixth process for producing an optically active 4,4,4-trifluoro-1,3-butanediol includes reducing the optically active aryl ester derivative by a hydride. A seventh process for producing an optically active or inactive 4,4,4-trifluoro-3-hydroxybutyric acid alkyl ester derivative includes reacting under an acid condition the optically active or optically inactive aryl ester derivative with a lower alcohol. It is possible to suitably combine at least two of the first to seventh processes.
Process for producing 4,4,4-trifluoro-3-hydroxybutyric acid derivatives
申请人:——
公开号:US20020016511A1
公开(公告)日:2002-02-07
A first process for producing an optically active perfluoroalkylcarbinol derivative includes (a) reacting an optically active imine with a compound that is a hemiacetal of a perfluoroalkylaldehyde or a hydrate of a perfluoroalkylaldehyde to obtain a condensate; and (b) hydrolyzing the condensate under an acid condition. A second process for increasing optical purity of an optically active 4,4,4-trifluoro-3-hydroxy-1-aryl-1-butanone derivative includes (a) precipitating a racemic crystal of the derivative, from the derivative; and (b) removing the racemic crystal from the derivative. A third process for increasing optical purity of the butanone derivative includes recrystallizing the derivative. Novel compounds are optically active and inactive 4,4,4-trifluoro-3-hydroxybutanoic aryl ester derivatives. A fourth process for producing an optically active or optically inactive 4,4,4-trifluoro-3-hydroxybutyric acid aryl ester derivative includes oxidizing an optically active or optically inactive 4,4,4-trifluoro-3-hydroxy-1-aryl-1-butanone derivative. A fifth process for increasing optical purity of the optically active aryl ester derivative includes recrystallizing the derivative. A sixth process for producing an optically active 4,4,4-trifluoro-1,3-butanediol includes reducing the optically active aryl ester derivative by a hydride. A seventh process for producing an optically active or inactive 4,4,4-trifluoro-3-hydroxybutyric acid alkyl ester derivative includes reacting under an acid condition the optically active or optically inactive aryl ester derivative with a lower alcohol. It is possible to suitably combine at least two of the first to seventh processes.