Desogestrel total synthesis

An ethynylcerium reagent was effectively utilized in the last step for the total synthesis of desogestrel 17.12 Desogestrel was isolated in 92% yield from the corresponding ketone 16, bearing acidic a-protons (Equation (2)). 

Corey, E. J., Huang, A. X. A Short Enantioselective Total Synthesis of the Third-Generation Oral Contraceptive Desogestrel. J. Am. Chem. Soc. 1999, 121,710-714. 

Corey has recently proposed a total synthesis, which gives in 14 stages en-antiomerically pure desogestrel in remarkably high yields. [60] This laboratory synthesis is still a long way from an industrial process (see the red markings), but it includes some synthetically interesting steps. 

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