TRANSFORMED STEROIDS .190. INFLUENCE OF CO-COMPLEXATION ON THE EPOXIDE RING-OPENING OF -ETHYNYL-16-ALPHA,17-ALPHA-EPOXYANDROST-4-EN-3-ONE ON REACTING WITH PYRIDINE HYDROFLUORIDE, PYRIDINE HYDROCHLORIDE, AND PYRIDINE THIOCYANATE

The epoxide ring opening of 16alpha, 17alpha-epoxy-17beta-ethynylandro st-4-en-3-one and its dicobalt hexacarbonyl complex on reacting with P y . HF, Py . HCl, and Py . HSCN was studied. The results of these reac tions and the structure of the end products depend wt only on the comp lexation of the acetylene bond, but also on the nucleophilic reagent u sed. On the basis of the reaction of a Co-coordinated 16alpha, 17alpha -epoxy-17beta-ethynylandrost-4-en-3-one there has been developed a pre parative method for the synthesis of pregn-4-ene-3,20-dione-[17alpha, 16alpha-d]-1',3'-oxazolidin-2'-one.