Process for preparing sulfonium or sulfoxonium salts of
申请人:Imperial Chemical Industries PLC
公开号:US05410074A1
公开(公告)日:1995-04-25
A compound of formula (I) ##STR1## where R.sup.1, R.sup.2, and R.sup.3 are alkyl or aralkyl or any two of R.sup.1, R.sup.2, and R.sup.3 together form a cycloalkyl ring and Y is S or S(O) is prepared by reacting N-phosphonomethylglycine with a compound of formula (II) ##STR2## where m is 0 or 1 in the presence of a base. A preferred compound of formula (I) is trimethylsulphonium N-phosphonomethylglycine and a preferred compound of formula (II) is trimethylsulphonium hydrogen sulphate.
Process for preparing epoxides from carbonyl compounds using sulphonium
申请人:Zeneca Limited
公开号:US05637727A1
公开(公告)日:1997-06-10
A process for transforming a carbonyl compound into its corresponding epoxide, which comprises contacting the carbonyl compound with either trimethylsulphonium hydrogen sulphate and/or bis(trimethylsulphonium) sulphate or trimethylsulphoxonium hydrogen sulphate and/or bis(trimethylsulphoxonium) sulphate, in the presence of a base.
Hydrolytic kinetic resolution of cyclic substrates
申请人:——
公开号:US20020032338A1
公开(公告)日:2002-03-14
The present invention relates to a process for stereoselective or regioselective chemical synthesis which generally comprises reacting a nucleophile and a chiral or prochiral cyclic substrate in the presence of a non-racemic, chiral catalyst to produce a stereoisomerically- and/or regioisomerically-enriched product. The present invention also relates to hydrolytic kinetic resolutions of racemic and diastereomeric mixtures of epoxides.
Nucleophilic kinetic resolution of cyclic substrates using silyl azides
申请人:——
公开号:US20040044233A1
公开(公告)日:2004-03-04
The present invention relates to a process for stereoselective or regioselective chemical synthesis which generally comprises reacting a nucleophile and a chiral or prochiral cyclic substrate in the presence of a non-racemic, chiral catalyst to produce a stereoisomerically- and/or regioisomerically-enriched product. The present invention also relates to hydrolytic kinetic resolutions of racemic and diastereomeric mixtures of epoxides.