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The steroidal 1,4-diphosphines 3alpha- and 3beta-diphenylphosphino-2alpha-(2′-diphenylphosphinoethyl)-5alpha-cholestanes and their 5H-benzophosphindole derivatives have been prepared and shown to be useful ligands in asymmetric hydrogenation reactions.Interestingly the 3alpha- and 3beta-derivatives lead to opposing enantioselection preferences when used in these reactions.A steroidal 1,3-diphospine, 3alpha-diphenylphosphino-2alpha-diphenylphosphinomethyl-5alpha-cholestane, has been prepared as a mixture containing some of the 3beta-epimer.The 3alpha-1,3-diphosphine led to similar enantioselection in hydrogenation reactions as the 3alpha-1,4-diphosphine, and a model is proposed to explain the sense of the enantioselectivity in the 1,4- and 1,3-diphosphines.A steroidal 1,6-diphosphine has also been prepared but leads to lower optical yields in the hydrogenation reactions.These ligands have been shown to lead to only poor to moderate optical yields when used in asymmetric carbon-carbon bond forming reactions.