Epoxide ring opening is a frequently required transformation in Organic Syn
thesis. In this paper we describe the application of NbCl5 for this purpose
using three different substrates. Chlorohydrins, 1,2-diols, products conta
ining solvent residues as well as rearrangement products are obtained, depe
nding on both the substrate structure and reaction conditions. Rationalizat
ions to account for some of the results are suggested.