Addition reaction of spiro orthoesters with electrophiles: A model reaction for the development of novel polyaddition accompanying ring‐opening isomerization

摘要: The addition reaction of spiro orthoesters (SOEs) with electrophiles accompanying ring-opening isomerization was investigated as a model for polyaddition bifunctional SOEs electrophiles. Among several such carboxylic acids and anhydrides, acid halides showed particularly high reactivities to SOEs. An equimolar chlorides took place selectively, leading the corresponding 1: 1 adducts. seven-membered cyclic ether rings-1,4,6-trioxaspiro[5.6]undecane derivatives-showed higher than six- five-membered rings. accompanied zero shrinkage in volume.