Zum verhalten von steroiddienen gegenüber Pb(OAc)4-n(N3)n

The reaction of 7-dehydrocholesterylbenzoate with the title reagent at a temperature of ?20° yields 50% 1, 3β-benzoyloxy-5α,14α-diazidocholest-7-en-6-one, and 25% 2, 3β-benzoyloxy-5α- azido-cholest-7-en-6-one. Under the same conditions 3,5-cholestadiene yields 3α,6β-diazidocholest-4- ene (40%; 3) and 6β-azido-cholest-4-en-3-one (6%; 4). The structure elucidation of the compounds 1–4 is supported by spectroscopy.