Flash vacuum pyrolysis of steroid esters

We report here our synthetic approach to acetylenic esters of six different steroids. The use of flash vacuum pyrolysis (FVP) is a very appealing tool for the acetylenic moiety to efficiently cyclize and rearrange which allows access to medicinally and pharmaceutically valuable products. Each substrate was subjected to FVP. The products were analyzed, identified and characterized. Acetylenic esters of aromatic steroids resulted in 2H-cyclohepta[b]furan-2-one, and 2H-chromen-2-one derivatives, while aliphatic esters afforded unsaturated polycyclic hydrocarbons via elimination of propiolic acid. [Display omitted] •Acetylenic aromatic steroid esters react via carbene insertion reactions.•FVP of steroid esters provides direct access to prepare interesting fused steroid derivatives.•Acetylenic aliphatic steroid esters undergo elimination reaction via six-membered transition state.