Palladium (0)-catalyzed asymmetric cycloaddition of vinyloxiranes with heterocumulenes using chiral phosphine ligands: an effective route to highly enantioselective …
C Larksarp, H Alper
文献索引：Larksarp, Chitchamai; Alper, Howard Journal of the American Chemical Society, 1997 , vol. 119, # 16 p. 3709 - 3715
Cycloaddition reaction of 2-vinyloxiranes with carbodiimides using Pd2 (dba) 3⊙ CHCl3, and TolBINAP as the chiral ligand, in THF at ambient temperature, afforded 4-vinyl-1, 3- oxazolidin-2-imines in 70− 99% yield and in up to 95% ee. The stereoselectivity is strongly influenced by the structure of the chiral phosphine ligands and substrates, as well as by the reaction conditions. The enantiodetermination step is assumed to be nucleophilic attack of ...
