Stereoselective Rearrangement of (Trifluoromethyl)prolinols to Enantioenriched 3-Substituted 2-(Trifluoromethyl)piperidines
摘要:
3-Substituted 2-(trifluoromethyl)piperidines B were synthesized by ring expansion of (trifluoromethyl)prolinols A, which were obtained from l-proline via an aziridinium intermediate C. The ring opening of the (trifluoromethyl)aziridinium intermediate by different nucleophiles is regio- and diastereoselective.
Stereoselective Rearrangement of (Trifluoromethyl)prolinols to Enantioenriched 3-Substituted 2-(Trifluoromethyl)piperidines
摘要:
3-Substituted 2-(trifluoromethyl)piperidines B were synthesized by ring expansion of (trifluoromethyl)prolinols A, which were obtained from l-proline via an aziridinium intermediate C. The ring opening of the (trifluoromethyl)aziridinium intermediate by different nucleophiles is regio- and diastereoselective.
Synthesis and utilization of trifluoromethylated amino alcohol ligands for the enantioselective Reformatsky reaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine
作者:Xiu-Hua Xu、Xiao-Long Qiu、Feng-Ling Qing
DOI:10.1016/j.tet.2008.05.043
日期:2008.7
successfully applied in the enantioselective Reformatskyreaction and addition of diethylzinc to N-(diphenylphosphinoyl)imine, respectively. The influence of the substituents on C-3 position and the amino moiety on the enantioselectivity has been carefully investigated. In the best cases, ligand 1b exhibited good selectivity for the enantioselective Reformatskyreaction in 86% ee and ligand 12d provided excellent