Method of synthesis of phosphinic acids based on hypophosphites: VIII. Synthesis of α-aminoalkylphenethylphosphinic acids

Development of methodology of double Arbuzov rearrangement based on hypophosphites allows a one-pot formation of two unsymmetrical phosphorus-carbon bonds by the Michael-Pudovik type reaction of stepwise addition of the intermediately forming silyl esters of trivalent phosphorus to different unsaturated compounds. A procedure was developed of the synthesis of α-aminoalkylphenethylphosphinic acids. Bis-(trimethylsilyl)phenethylphosphonite formed as a result of the addition of bis(trimethylsilyl)hypophosphite to styrene in situ was added without isolation from the reaction mixture to Schiff bases obtained preliminary from benzylamine or diphenylmethylamine and various aldehydes. The subsequent removal of N-protecting groups by hydrogenation or acidic hydrolysis gave a number of new α-aminoalkylphenethylphosphinic acids.