Hammett Studies of Enantiocontrol by PHOX Ligands in Pd-Catalyzed Allylic Substitution Reactions
作者:Ryan N. Constantine、Naomi Kim、Richard C. Bunt
DOI:10.1021/ol034610q
日期:2003.6.1
Electronically modified PHOX ligands 3a-e were synthesized to probe the mechanism of the enantioselective palladium-catalyzed allylicalkylation and amination reactions. Alkylation with dimethyl sodiomalonate produced only a small variation in the ee (89.3% to 93.4%), but amination with benzylamine gave a much wider variation in the ee (16.4% to 66.6%). Hammett analysis suggests that the substituents