Method of preparing .delta.5,7-steroids

Abstract From the Canadian patent

The invention relates to a method of preparing .DELTA. 5,7-steroids, in particular 7-dehydrocholesterol compounds of the general formula, wherein R is a hydrogen atom a hydroxy group, optionally etheri-, fied with a C1-C4 alkanol or esterified with a C1-C4 alkane carboxylic acid, a C2-C5 alkanoyl group optio-, nally ketalized with a C1-C4 alkanol or a branched, or non-branched, saturated or unsaturated C1-C10 alkyl group, optionally substituted with one or more fluorine atoms or hydroxy groups, which hydroxygroup or groups is (are) optionally etherified with C1-C4 alkanol(s) or esterified with C1-C4 alkane carboxylic acid(s) and, R1, R2 and R3 are equal or different and represent hydrogen …