ALLYLIC STEROID ALCOHOLS. Ⅱ. METHOXYLATION OF THE EPIMERIC 3-HYDROXYCHOLEST-4-ENES IN THE MEDIUM OF METHANOL-HYDROCHLORIC ACID.
It was established that 3α-hydroxycholest-4-ene in methanol containing a trace of acid was converted into the corresponding 3α-methyl ether with a great ease and the ether was readily interconverted into the 3β-epimer in the solvent. The same treatment for 3β-hydroxycholest-4-ene was also carried out, yielding 3βmethyl ether as the major component, but the 3α-methyl ether in the reaction mixture enhanced along with increasing reaction time. The evidence of the structures of 3α- and 3β-methyl ethers was obtained from isolation of respective products and their characterization by means of the differences in [M］D, NMR and mass spectrometry.