Synthesis of various organophosphonates from diethyl 1-(trimethylsilyl) vinylphosphonate

Abstract

Dialkyl 1-(trimethylsilyl)alkenylphosphonates were synthesized by direct coupling of dialkylphosphites and (E)-1-(trimethylsilyl)alkenyl halides in the presence of triethylamine and a catalytic amount of tetrakis(triphenylphosphine) palladium. Organometallic reagents readily added to diethyl 1-(trimethylsilyl)vinylphosphonate by virtue of the polarizing silyl group to give the stable intermediate anions. It was quenched with acetic acid, methyl iodide, and carbonyl compounds, to achieve synthetically useful diethyl alkylphosphonates and diethyl alkenylphosphonates respectively. Quenching with acyl halides and isocyanates to afford, α-alkyl substituted β-keto phosphonates and alkylphosphono-amides respectively.