Preparation of Steroid Olefins from Heptafluorobutyrates
作者:Lucie Dalibová、Ladislav Kohout
DOI:10.1135/cccc19980549
日期:——
Steroids with hydroxyl group in positions 2, 3, 6, 7, 17 and 20 were esterified with heptafluorobutyric anhydride. The obtained esters on treatment with lithium bromide in N,N-dimethylacetamide in the presence of pyridinium tosylate afforded the corresponding olefins in high yields.
Hydroxy-steroids. Part XI. The preparation and infrared spectra of vicinal cholestanediols
作者:C. W. Davey、E. L. McGinnis、J. M. McKeown (née Chancellor)、G. D. Meakins、M. W. Pemberton、R. N. Young
DOI:10.1039/j39680002674
日期:——
Twenty-eight vicinal cholestanediols (positions 1,2; 2,3; 3,4; 4,5; 5,6; 6,7; and 7,8) have been prepared by unambiguous routes starting from the corresponding olefins. The O–H stretching bands of dilute solutions of these diols and of seven reference compounds have been examined under high dispersion. Characteristic differences between ax,ax, ax,eq, and eq,eq compounds were observed. It was concluded
The reaction of the following steroidal olefins with iodine–copper(II) acetate in acetic acid afforded the corresponding steroidal trans-iodo acetates: 5α-cholest-1-, -2-, and -3-ene; and 5β-cholest-1-, -2-, and -3-ene.
Steroids and Walden inversion. Part LXI. Chlorination of 5α-cholestan-2-one
作者:C. W. Shoppee、S. C. Sharma
DOI:10.1039/j39670002385
日期:——
Monochlorination of 5α-cholestan-2-one yields 78% of the axial 3α-chloro-ketone, 19% of the equatorial 3β-chloro-ketone, and a little of the 3,3-dichloro-ketone under conditions in which the 3α-chloro-ketone is stable. Chlorination of the enol acetate of 5α-cholestan-2-one affords 3α-chlorocholestan-2-one, with traces of the 3β-chloro-ketone. 1α-Chloro-, 1α,3α-dichloro-, 1α,3β-dichloro-, 3,3-dichloro-