References
- Djerassi , C. 1963 . “Steroid Reactions,” , 92 San Francisco : Holden-Day Inc. .
- Fried , John and John Edwards , A. , eds. 1977 . “Organic Reactions in Steroid Chemistry” , Vol. 1 , 234 N.Y. : Van Nostrand Reinhold Co. .
- Chakravarti , D. , Chakravarti , R. N. and Mitra , M. N. 1962 . Nature , 193 : 1071
- Klelderer , E. C. and Kornfeld , E. C. 1948 . J. Org. Chem. , 13 : 455
- Kleiderer , E. C. , Rice , J. B. , Conquest , V. and Williams , J. H. 1945 . “Pharmaceutical Activities at I.G. Farbenindustrie Plant, Hochst am Main,” , U. S. Dept. of Commerce, Office of the Publication Board . Report PB981
- Products were identified by comparison of glpc retention times with those of known samples
- Forsek , J. 1980 . Tetrahedron Lett. , 21 : 1071
- Foster , C. H. U. S. Patent 4,235,791 . 1980 . to Eastman Kodak Company
- With some batches of catalyst, the reaction was observed to be very slow, apparently because of a catalyst that was too inactive. An inactive batch of catalyst could be used effectively by adding a small amount (∼ 10%) of an ordinary grade (e.g. Degussa type BKlllw) of Raney nickel to the reaction mixture prior to reaction.
- CAUTION: The flask was equipped with a foam trap as the presence of H20 in the mixture sometimes caused severe bumping of the hot reaction mixture.
- In some cases the sterols used apparently had impurities present that catalyzed dehydration at the temperature required for dehydrogenation. When this was observed, the addition of a small amount of K2CO3 to the reaction mixture gave higher yields.
- Raney nickel (No. 28) purchased from W. R. Grace.