Studies on Organic Fluorine Compounds. XXXIX. Studies on Steroids. LXXIX. Synthesis of 1α, 25-Dihydroxy-26, 26, 26, 27, 27, 27-hexafluorovitamin D₃

Abstract

1α, 25-Dihydroxy-26, 26, 26, 27, 27, 27-hexafluorocholesterol was synthesized by two procedures. Cholenic acid was converted to the 1α-hydroxy-24-sulfone derivative and hexafluoroacetone was reacted with the lithiated 24-sulfone. Subsequent removal of the sulfonyl group afforded the hexafluoro-1α, 25-dihydroxy compound. An alternative process consists of construction of the hexafluoro-25-hydroxy part on the side chain followed by the introduction of a hydroxy group at the 1α-position. The hexafluoro derivative was converted to the vitamin D form, 1α, 25-dihydroxyhexafluorovitamin D₃, via the corresponding 5, 7-diene.