Abstract Unsubstituted medium-ring 1, 2-epoxycycloalkanes and certain vic-epoxyalkanes are reduced to the corresponding alcohols very slowly when LiAlH 4 alone is used as reducing agent. However, the combination of LiAlH 4 and AlCl 3, in a 2: 1 molar ratio (with respect to 1 mol-equiv. of epoxide) used in refluxing Et 2 O, greatly enhances these reductions, rendering them of interest for practical purposes.