| abstract |
A novel phosphine compound having excellent properties (chemical selectivity, enantioselectivity, catalytic activity) as a catalyst for asymmetric syntheses, especially asymmetric hydrogenation. A phosphine-phosphorane compound represented by the following general formula: n n n (wherein R 1 represents hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, R 2 , R 3 , R 4 , and R 5 are the same or different, and each represents hydrogen atom, or an alkyl group having 1 to 6 carbon atoms, etc., and each of R 2 and R 3 , R 3 and R 4 , and R 4 and R 5 may be together combined to form a ring which may contain one or more (preferably 1 to 2) oxygen atoms, and R 6 and R 7 are the same or different, and each represents a linear or branched alkyl group having 1 to 6 carbon atoms, etc.). |