Diacetoxy bisnor cholanyldiphenylethylene

12-Diacetoxy-bisnor-cholanyldiphenylethylene. A solution of phenylmagnesium bromide is prepared in a 5-1. three-necked flask, fitted with a dropping funnel, efficient reflux condenser, and mechanical stirrer, from 97.2 g. (4 gram atoms) of magnesium, 

The crude carbinol is acetylated and dehydrated by refluxing its solution in 1 1. of glacial acetic acid and 500 ml. of acetic anhydride for 1 hour. The solution is then concentrated to about 500 ml. by distillation. After cooling overnight, the crystalline 3,12-diacetoxy-J M0r-cholanyldipheny] ethylene is collected on a filter and washed with acetic acid. The yield is 95-105 g. (G3.5-70.0%) of material melting at 154-157° (Note 5). This product is sufficiently pure to be used for the preparation of Mor-desoxycholic acid (p. 38) one crystallization from acetone gives white crystals which melt at 156-157.5° fully purified material melts at 159.5-160.5°. 

A good grade of desoxycholic acid should be used. The product from Wilson Laboratories has been found to be satisfactory. 

At this point the solution should be filtered if any insoluble material is present. 

This methyl desoxycholate is pure enough for most purposes, but if desired it may be recrystallized from methanol or from a mixture of ether and petroleum ether. 

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