A New P,S-Chiral Auxiliary Derived from Thioglucose. X-ray Structure of a Palladium 1,3-Diphenylallyl Complex with a Strongly Rotated Allyl Ligand

The new ferrocene-based P,S-chiral auxiliary 1, derived from thioglucose, has been prepared and used in the palladium-catalyzed enantioselective allylic alkylation reaction. The X-ray structure of the allyl cationic complex [Pd(η3-PhCHCHCHPh)(1)]CF3SO3 (2) reveals a markedly rotated 1,3-diphenylallyl ligand such that the terminal allyl carbon C(3), trans to the phosphorus donor, is ca. 0.85(3) Å below the coordination plane. This distortion is pertinent to the Pd(0) transition state complex expected in the allylic alkylation reaction