Sodium hydride → 1alpha,3beta-bis(tert-butyldimethylsilyloxy)-20-{4-triethylsilyloxy-4-methyl-(2E)-pentenyloxy}-20-methylpregna-5,7,16-triene

Participants

Reaction Steps

1α,3β-Bis(tert-butyldimethylsilyloxy)-20-hydroxy-20-methylpregna-5,7,16-triene (103 mg, 0.180 mmol), 1-bromo-4-triethylsilyloxy-4-methyl-(2E)-pentene (211 mg, 0.719 mmol), sodium hydride (60% in oil, 43 mg, 1.08 mmol), 15-crown-5 (40 mg, 0.182 mmol) and tetrahydrofuran (3 ml) were subjected to reaction using a procedure similar to that of Example 5(1) (reflux under heating for 6 hours), worked up and purified by column chromatography (hexane:toluene=2:1) to give the titled compound (140 mg, 99%) as a colorless solid.

Provenance & Evidence