Syntheses of Novel Sugar Phosphine Derivatives, and Homogeneous Hydrogenation Reactions with Their Rhodium Complexes

抄録

Optically active diphenylphosphine derivatives, (1R, 3R, 4S, 5R, 6R)-6-cyano-5-diphenylphosphino-3, 4-O-isopropylidene-2-oxabicyclo [3.2.0] heptane-3, 4-diol (15) and its reduction product (17), were prepared by the cyclization of 12 or 13, which was obtained from a common sugar, D-glucose. These phosphines were used as ligands in the rhodium complex-catalyzed asymmetric hydrogenation of prochiral olefins. The rhodium complex catalyst which was constructed with 2 mol of 15 and 1 mol of rhodium (cyclooctene)₂Cl (20) worked efficiently for the asymmetric hydrogenation of α-acetamidocinnamic acid (18) and itaconic acid (24) with 91.6% ee-(S) and 69.6% ee-(R), respectively. On the other hand, the rhodium complex constructed with 1 mol of 17 and 1 mol of 20 was less effective than that of 15, giving 39.0% ee-(R) in the reaction with 18. Methyl esters of 18 and 24 were also hydrogenated using the complex of 15.