Binary Regiocontrol in the Reaction between Pentadienyltin and Imines by Lewis Acids and NSubstituents

Binary regiocontrolled pentadienylation of imines with a pentadienyltin reagent was achieved. While N-phenyl imines afforded (epsilon)adducts (1,3-dienes) exclusively under Lewis acidic conditions, the combination of N-tosyl imines and indium or zinc chloride as a Lewis acid gave (gamma)-adducts (1,4-dienes) preferentially.