alpha-bromo-alpha,alpha-difluoroallyl derivatives as synthetic intermediate: Nucleophilic substitution of alpha-bromo-alpha,alpha-difluoroallyl derivatives in the presence of palladium catalysts

The palladium catalyzed nucleophilic substitution of alpha-bromo-alpha,alph a-difluoroallyl derivatives turned out to be an efficient method for the pr eparation of several fluorinated organic molecules. Several soft carbon nuc leophiles regioselectively reacted with 3-bromo-3,3-difluoropropene (BDFP) to give the 3-substituted 1,1-difluoroalkenes. Phenylzinc chloride and trib utylphenyltin afforded 1-fluoro-1,3-diphenylpropene. The radical brominatio n of 3-substituted 1,1-difluoroalkenes provided 1-substituted BDFPs, and a 1-substituted BDFP reacted with carbon nucleophiles to give 1,3-disubstitut ed 3,3-difluoroalkenes For the reaction of nitrogen nucleophiles with BDFP, an amine and the sodium salts of the carbamates reacted with BDFP at the g amma-position, However, the sodium salts of the sulfoneamide predominantly attacked at the alpha-position.