Abstract A literature survey indicated that stereospecific non-reductive β-face methylation at C (10) of steroidal synthesis intermediate BCD-tricyclic 9-en-5-ones had never been effected. An attempt to define the factors controlling the β/α product ratio in such alkylations was made. The course of methylation is significantly affected by the temperature. In the best case, methylation of the sodium enolate of 17 β-t-butoxy-19-(3, 5-dimethyl-4-isoxazolyl)- ...
