Grundmann's Ketone Research Articles

Calciferol and its relatives. Part 22. A direct total synthesis of vitamin D2 and vitamin D3

Direct total syntheses are described of 3-deoxyvitamin D2, vitamin D2, and vitamin D3. For the first, the lithio-derivative of (Z)-2-(2-methylenecyclohexylidene)ethyl(diphenyl)phosphine oxide and the Windaus–Grundmann ketone C19H32O were the reacting partners; for the second, the same ketone and the lithio-derivative of a protected form of (S)-(Z)-2-(5-hydroxy-2-methylenecyclohexylidene)ethyl(diphenyl)Phosphine oxide; and for the third, the same lithio-derivative and des-AB-cholestan-8-one. In these reactions, the original Z-allyl geometry of the phosphine oxides was completely preserved in the 5,6-double bond of the products, and the new (7,8-) double bond was formed with exclusive E-geometry.

Calciferol and its relatives. Part 20. A synthesis of Windaus and Grundmann's C19 ketone

Starting from 1β-[(R)-2- hydroxy-1-methylethyl]-7aβ-methyl-3aα,6,7,7aβ-tetrahydroindane (1) syntheses have been effected of two bicyclic compounds suitable as intermediates for conversion into vitamin D-active products, viz. Windaus and Grundmann's ketone (20){7aβ-methyl-1β-[(1R,4R)-1,4,5-trimethylhex-trans-2-enyl]-3aα,4,5,6,7,7aβ-hexahydroindan-4-one}, and des-AB-cholestane-8β,25-diol (23){4β-hydroxy-1β-[(R)-5-hydroxy-1,5-dimethylhexyl]-7aβ-methyl-3aα,4,5,6,7,7aβ-hexahydroindane}.