摘要:
The TiCl4-catalyzed Evans-aldol reaction of optically active 3,3,3-trifluoropropanoic imide gave the non-Evans syn product stereoselectively, whereas the Reformatsky reaction of 2-bromo-3,3,3-trifluoropropanoic imide in the presence of Et3Al led to the Evans anti product. These new approaches enabled us to synthesize all stereoisomers of trifluoromethylated aldol products for the first time.