Reaction of glycidol with dichloroethers: cyclic and acyclic ortho ester formation

The interaction of stoichiometric quantities of glycidol with alkyl dichloromethyl ethers in the presence of 2 equiv. of NEt₃ in diethyl ether leads to formation of diglycidyloxy alkoxy methanes whereas the same reaction involving equimolar quantities of the reagents in benzene in the presence of 1 equiv. of NEt₃ leads to formation of 4-chloromethyl-2-alkoxy-1,3-dioxolanes.