Raju, N. M.; Rajasekhar, K.; Babu, J. M.; Rao, B. V. Synthesis of 4-Chloro-5,6-Dihydro-2H-Pyran Derivatives by NbCl5 Mediated Cyclization of Epoxides With Homopropargylic Alcohols. ajc 2016, 29, 614-616.