Zur gezielten Oxidation der Δ7-Doppelbindung in den 4-Phenyl-1,2,4-triazolin-3,5-dion-Addukten des Vitamin D3

The possibility of regio- and stereospecific oxidation of the 7-double bond of the 4-phenyl-1,2,4-triazolin-3,5-dione adducts1 a and1 b of Vitamin D₃ is reported. Oxidation of the corresponding benzoates2 a and2 b withm-Chlorperbenzoic acid yields the two oxirans3 a and3 b which in turn with NaI-CH₃COOH-Zn after saponification to5 a and5 b lead to the allylic alcohols6 a and6 b.