Chiral vicinal diamines as promising ligands in Pd-catalyzed reductive Heck type cyclizations

Palladium complexes with inexpensive and available vicinal diamines can serve as catalysts for the reductive Heck-type cyclization. o -Bromo- N -(2-phenylallyl)anilides are converted into the corresponding 3-methyl-3-phenylindolines, the analogous cyclization occurred for 2-bromo-4-methylphenyl 2-phenylallyl ether and N -(2-bromophenyl)-2-phenylacrylamides. The use of (1 R ,2 R )- N , N’ -dibenzylcyclohexane-1,2-diamine provides up to 35% ee of the indolines; this is the first case of asymmetric induction during the reductive Heck reaction involving diamine complexes.