Methanol → HCID 53993440, compound

Participants

Reaction Steps

36.1 g (0.093 mole) of 3β-hydroxy-5-cholenic acid methyl ester was dissolved in 722 ml of dioxane at room temperature, and 1.81 g (0.05 mole of p-toluenesulfonic acid was added. Then, 26.83 ml (0.294 mole) of dihydropyrane was added dropwise over a period of 10 minutes. The temperature rose to 23°-27° C. The solution was stirred for two more hours at room temperature and then adjusted to pH 8 with 3.4 ml of a mixture of 1:1 methanol 29% ammonium hydroxide. An oily precipitate began forming. A semi-solid residue was obtained after the solvent was evaporated. The residue was dissolved in 1.1 liters of chloroform, washed with a 15% sodium bicarbonate solution, then with water. The chloroform solution was dried, decolorized with charcoal and evaporated. The solid residue was dissolved in 1.5 liters of boiling methanol, allowed to cool to room temperature and then filtered. The dried product weighed 34.5 g, mp 114°-115° C. (989-161-A). From the filtrate an additional amount of 8.0 g was isolated, which was recrystallized again from methanol and then from n-heptane. The second crop was 4.1 g, making a total of 38.6 g of 3β-(2-tetrahydropyranyloxy)-5-cholenic acid methyl ester, yield 84%. Anal. Calcd for C30H48O4, M. W. 472.715: C, 76.22; H, 10.24; O, 13.54. Found: C, 76.37; H, 10.21; O, 13.28 (989-161-A). NMR (989-157-A) (CDCl3): δ5.22-5.43 (m,1H, vinyl), ##STR17## 3.20-4.10 (br m, 3H, adjacent to oxygen), 3.63 (s, 3H, --OCH3), 1.00 (s, 3H, C-19 --CH3), 0.66 (s, 3H, C-18 --CH3). IR (989-157-A) (CHCl3) 2940, 2860, 1730, 1440, 1170, 1135, 1110, 1075, 1030, 1020 cm-1.

Provenance & Evidence