Regio- and diastereoselective nucleophilic substitution of 2-methylacetoacetate with a chiral non-racemic π-allyl Pd complex creates consecutive chiral non-racemic quaternary and tertiary carbon centers. σ-Bond formation between the re-face of the π-allyl Pd complex and the re-face of the enol acetoacetate was controlled by the o-(diphenylphosphanyl)arylcarboxylic acid ligand selectively. (−)-Acetomycin was synthesized in seven steps using this key approach. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)