Efficient Synthesis of Symmetrical α,α-Disubstituted β-Amino Acids and α,α-Disubstituted Aldehydes via Dialkylation of Nucleophilic β-Alanine Equivalent

Homologation of the nucleophilic beta-alanine equivalent beta-Ala Ni(II)-PABP [Ni(II) complex of beta-alanine Schiff base with 2-[N-(alpha-picolyl)amino]benzophenone (PABP), 1] via alkyl halide alkylation was systematically studied as a general method for preparing symmetrically alpha,alpha-disubstituted beta-amino acids. The dialkylation reactions could be easily performed and did not require inert atmosphere, dried solvents, and low temperatures, thereby affording the benefits of operationally convenient experimental procedure and high atom economy. Further, the methodology developed by us can also be used to generate symmetrical alpha,alpha-disubstituted aldehydes through an alternative decomposition method.