Abstract
The reactions of cholesterol (I) with hydrogen peroxide in the presence of transitionmetal salts were carried out at moderate temperature in an acetonitrile medium. When ferrous or titanous sulphate was employed, 5, 6α-epoxy-5α-cholestan-3β-ol (II) (and/or epimeric β-epoxide, XII), 5α-cholestane-3β, 5, 6β-triol (III), cholest-5-ene-3β, 7α-diol (IV), and cholest-5-ene-3β, 7β-diol (V) were formed in rather poor yields. The radical scavenger, α-tocopherol, inhibited the hydroxylation at the allylic position and thus no formation of IV and V was observed. On the contrary, titanium trichloride-hydrogen peroxide system was found to consume entirely the substrate (I) giving considerable amounts of III and the chlorinated products such as 5, 6β-dichloro-5α-cholestan-3β-ol (VI), 5-chloro-5α-cholestane-3β, 6β-diol (VII), 6β-chloro-5α-cholestane-3β, 5-diol (VIII), and 6α-chloro-5β-cholestane-3β, 5-diol (IX). The epoxides (II and XII) were separated solely as the artifacts from the monochlorides (VII and VIII) through column chromatography on alumina. The yields of III, VI, the mixture of VII and VIII, and of IX were in an approximate ratio of 2 : 1 : 2 : 4.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.