Reactions of 5α-hydroxy steroids part VI a back-bone rearrangement of 3β, 5α, 6β-triacetoxycholestane

✍ Scribed by J.W. Blunt; M.P. Hartshorn; D.N. Kirk

• Publisher: Elsevier Science
• Year: 1966
• Tongue: French
• Weight: 140 KB
• Volume: 7
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)72809-7

✦ Synopsis

Snatzlce and Pehlhaber' reported the isolation, in yields up to 5C$, of an unsaturated diaoetate on treatment of the triacetate (I) with acetic anhydride in the presence of a variety of acidic catalysts at 80' or 440'. Theee authors tentatively assigned structure (II) to the diacetate but later commented (as a footnote) that the masa spectrum suggested an i8-nor-+-methyl-613(14) -partial etructure. This unsaturated dlacetate ia now shown to have structure (IIIa) In which the steroid skeleton haa undergone a back-bone rearrangement. The assigned structure is supported by ultraviolet and N.M.R. spectra and oonverelon into a known compound.

In particulaqthe ultraviolet spectrum (e2050, ?1,200; e2,00, 8,300; e2,50p 5,300; e22009 2,600) ie consistent with a tetrasubstituted double bond, exooyolic to at leaet one ring; the absence of vinylic protone ie confirmed by the N.M.R. spectrum.