Meystre-Miescher-Wettstein degradation

A variation of this procedure, the Meystre-Miescher-Wettstein Degradation (Miescher Degradation) removes three carbons from the chain ... 

A further advance of major importance in the practical utilization of the bile acids for cortisone syntheses was the replacement of the laborious Barbier-Wieland degradation (cf. Fig. 2) by the Meystre-Miescher degradation. As applied by Wettstein and Meystre (1947) to methyl 3a-acetoxy-ll-ketocholanate (VI, R = Ac R = CH3), this procedure involves reaction with phenylmagnesium bromide and acetylation to produce the diphenyl olefin (IX), which upon bromination with N-bromo-suooinimide and dehydrobromination smoothly yields the diene (X). 

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See also in sourсe #XX -- [ ]

See also in sourсe #XX -- [ ]

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