Sometime ago it was reported that pentaethoxyphosphorane and diethoxytriphenylphosphorane can effect the cyclization of various substituted alcohols to heterocycles. These reactions proceeded smoothly at room temperature and required no catalysis or blocking groups.'More recently Evans and co-workers2 have utilized diethoxytriphenylphosphorane to cyclize a variety of diols to cyclic ethers. The major ...
