Convenient Synthesis of 1-(Trimethylsilyl)- and 1-(Trimethylstannyl)vinylphosphonates and Their Synthetic Application

Dimethyl 1,1-bis(trimethylsilyl)methylphosphonate was succeeded to react with aromatic aldehydes in the presence of methyl benzoate as additive to give the corresponding vinylphosphonates in moderate yields. Michael addition and subsequent Peterson olefination reaction of dimethyl (Z)-2-(3,4-methylenedioxyphenyl)-1-(trimethylsilyl)vinylphosphonate with 3,4,5-trimethoxyphenyllithium and crotonaldehyde afforded the corresponding (2E,4E)-1-(3,4,5-trimethoxyphenyl)-1-(3,4-methylenedioxyphenyl)-2-(dimethylphosphono)hexa-2,4-diene in 36% yield.