The mechanism and origin of enantioselectivity of palladium-catalyzed redox-relay Heck arylation of 1,1-disubstituted homoallylic alcohols were investigated computationally. The computed mechanism consists of an initial migratory insertion, followed by a β-hydride elimination, and a subsequent re-insertion/elimination process to yield an enol intermediate, which tautomerizes to the more stable carbonyl product. Results from DFT calculations suggest that the key enantiodetermining step is the reinsertion of an alkene intermediate into the Pd-H bond, but not the initial migratory insertion of the substrate into the Pd-Aryl species. By comparing two chiral pyridine oxazoline ligands with a focus on the phenyl