디에틸시클로헥실라미노비닐포스페이트

Preparative Methods of Diethyl β-(Cyclohexylimino)ethylphosphonate: (EtO)2CHCH2P(O)(OEt)2 is prepared by reaction of Triethyl Phosphite with BrCH2CH(OEt)2. Acetal hydrolysis affords diethyl formylmethylphosphonate, which is combined with an equimolar quantity of cyclohexylamine in MeOH. The product is isolated by fractional distillation in the presence of K2CO3, to prevent acid-catalyzed dimerization, and at reduced pressure, followed by crystallization from cold pentane.[1b] Yields are 65-75%. A modified procedure for imine formation uses MeCN as solvent with isolation of product from Et2O at -40 °C to afford white crystalline material in 70% yield.[2]