Synthesis of vinyl selenides and ketene selenoacetals via wittig - horner reaction

Abstract

The Convenient preparations of vinyl selenides and ketene selenoacetals were studied. Reaction of the lithio anions derived from diethyl alkylphosphonates with phenylselenenyl bromide give the diethyl phehylselenoalkylphosphonate anion. In situ reaction with aldehyde or ketones gives vinyl selenides in a convenient one- pot procedure. Diethyl 1,1- bis(phenylseleno)methylphosphonate was prepared from diethyl methylphosphonate and phenylselenenyl bromide. And its reactions with aldehydes and ketene are investigated. The products formed with aldehydes are ketene selenoacetals. With ketones the reaction takes an unexpected route and the major products are the α- phenylselenoketones.