Preparation of Chiral Diphenylphosphines from D-Glucose and Enantioselective Hydrogenation with Their Rh(l) Complexes
نویسندگان
چکیده
(2R,3S)-2-Methylsulfonyloxymeihyl-3-methylsulfonyloxy-tetrahydropyran (4), derived from n-glucose, is diphenylphosphinated to (2R,3R)-2-diphenylphosphinomethyl-3-diphenylphosphino-tetrahydropyran (7), which is formed as aminor product. Compound 8 is the predominant product, formed on 3,4-elimination. Preparation and characterization of the rhodium(I) complexes 10-12 is described. Complex 10 of bidentate Iigand 7 exhibits in hydrogenation of Z-a-N-acetylaminocinnamic acid enantioselectivity comparable to that obtained with rhodium(I) complex of (-)-DIOP (-70010e. e.). Saturated monophosphine, (2S)-2-diphenylphosphinomethyl-tetrahydropyran (9) affords mixed rhodium(I) complex (11, 12), which exhibits low enantioselectivity.
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