A New Asymmetric Synthesis of Tricarbonylchromium Complexes of ortho‐Substituted Benzaldehydes. Preliminary communication

Abstract ortho‐Substituted [Cr(CO)3(benzaldehyde)] complexes are obtained via nucleophilic addition of alkyl‐ and aryllithium reagents to a [Cr(CO)3(phenylmethaneimine)] complex followed by endo‐hydride abstraction with triphenylmethyl cation. This sequence, when carried out with a [Cr(CO)3(benzaldehyde SAMP hydrazone)] complex affords substituted derivatives (Me, Bu, Ph, vinyl) with high (⩾97%) diastereoselectivity and, after hydrolysis, ortho‐ substituted [Cr(CO)3(benzaldehyde)] ((S)‐1) complexes of high enantiomeric purity.