Addition of Diethylzinc to Aryl Aldehydes Catalyzed by (1S,3S)-N,NI-bis-1,3-Diphenyl-1,3-Propanediamine and its Dilithium Salts: a Mechanistic Rationale Investigation.

Article abstract of DOI:10.1016/S0040-4020(01)80230-1

N,N^I-bis benzyl substituted 1,3-diamine 1a, synthesized in high optical purity, and the corresponding dilithium salt 1b are used, for the first time, as chiral catalysts in the addition of ZnEt2 to aromatic aldehydes.Both 1a and 1b are able to promete the reaction but the products obtained exhibited low enantiomeric excesses.By 1H NMR and UV-CD investigation, experimental evidences about the structure of some reaction intermediates have been gained: reaction pathway consistent with spectroscopic data, chemical and stereochemical results could be postulated.