Stereospecific Preparation of F-Alkenyl Cadmium Reagents Directly from F-Alkenyl Iodides and Bromides and Cadmium Metal

摘要

F-Alkenyl cadmium reagents can be readily prepared via the direct reaction of F-alkenyl iodides or bromides with cadmium powder in DMF at room temperature to 60 C. The reactions proceed with total retention of configuration, and subsequent functionalization processes also proceed with stereochemical control. The thermal stability of the cadmium reagents is excellent, and the bis reagent (Z-CF3CF=CF)2Cd was isolated (via distillation) as a DMF or triglyme solvate. This approach provides a facile, easily scaled up, stereospecific, one-pot procedure to these stable alkenyl synthetic reagents.