The synthesis of 5β,6β-epoxides is a useful reaction since this group is present in many biologically active steroids. Chandrasekaran et al. and more recently a number of other groups including ourselves, demonstrated that these epoxides can be obtained from D⁵-steroids using biphasic systems involving potassium permanganate and metal salts. Recently the β-epoxidation of D⁵-steroids using ketones as catalysts and oxone as the terminal oxidant was reported. The use of molecular oxygen or air as the oxidant in the presence of either metalloporphyrin or Mn(II), Ni(II), Fe(III) and Co(II) complexes as catalysts is of greater industrial interest, but a difficult separation step is needed to remove the catalyst which cannot easily be reused. Here we report the use of some heterogeneous cobalt catalysts for the 5β,6β-epoxidation of D⁵-steroids under Mukaiyama reaction conditions (Scheme 1).