Pyridine → 19-Trimethylsiloxy-4-androstene-3,17-dione

Reaction equation

[OH:1][CH2:2][C@@:3]12[C@@H:20]3[C@H:11]([C@H:12]4[C@@:16]([CH2:18][CH2:19]3)([CH3:17])[C:15](=[O:21])[CH2:14][CH2:13]4)[CH2:10][CH2:9][C:8]1=[CH:7][C:6](=[O:22])[CH2:5][CH2:4]2.[CH3:23][Si:24]([CH3:27])([CH3:26])Cl.N1C=CC=CC=1>C1C=CC=CC=1>[CH3:23][Si:24]([CH3:27])([CH3:26])[O:1][CH2:2][C@@:3]12[C@@H:20]3[C@H:11]([C@H:12]4[C@@:16]([CH2:18][CH2:19]3)([CH3:17])[C:15](=[O:21])[CH2:14][CH2:13]4)[CH2:10][CH2:9][C:8]1=[CH:7][C:6](=[O:22])[CH2:5][CH2:4]2

Participants

Procedure

A mixture of 9.0 gm (0.03 mole) of 19-hydroxy-4-androstene-3,17-dione, 4.3 gm (0.04 mole) of trimethylchlorosilane and 3.2 gm (0.04 mole) of pyridine is refluxed in 100 ml of benzene for a period of 18 hours. The resulting suspension is filtered, the volatiles removed in vacuo and concentrated to a yellow oil. The oil is placed upon a silica gel chromatographic column packed in chloroform and eluted with chloroform. The chloroform eluate is evaporated to dryness in vacuo and the residue is recrystallized twice from hexane to yield the desired 19-(trimethylsiloxy)-4-androstene-3,17-dione having a m.p. of 87°-9° C., uv max (MeOH) 242 nm (ε14,700).