Steroid-hindered 17 beta-tertiary alcohol: characterization of dehydrated compounds.

Five dehydrated compounds obtained from a tert-butyldimethylsilylchloride/imidazole or an aqueous hydrochloric acid treatment of 17 alpha-butyl-3-O-methyl estradiol in refluxing solvent were purified and characterized. Three compounds were obtained from a direct vicinal proton elimination, the two others from a vicinal elimination after migration of methyl-18. Depending on the treatment, the proportions of dehydrated compounds are different. In addition, a general profile of experimental conditions providing a similar mixture of dehydrated compounds was also established for this steroid-hindered 17 beta-tertiary alcohol.