| Research Abstract |
Preparation of ruthenium complexes with chiral ligands, and the asymmetric radical reactions in the coordination sphere using these complexes as a catalyst have been investigated. Such ruthenium complexes with chiral ligand as <Ru_2> <Cl_4> <[(+)-DIOP]_3> , <Ru_2> <Cl_4> <[(-)-DIOP]_3> , <Ru_2> <Cl_4> <[(+)-BINAP]_3> ( <NET_3> ), <Ru_2> <Cl_4> <[(-)-BINAP]_3> ( <NET_3> ), and <Ru_2> <Cl_4> <[(-)-BPPM]_3> ( <NET_3> ) were prepared. I have already established the <RuCl_2> - <(PPh_3)_3> catalyzed reactions of arenesulfonyl chloride with olefins proceeded smoothly by radical reaction mechanism in the coordination sphere of the ruthenium complex to give 1:1 adducts in high yields. The ruthenium complexes with chiral ligands prepared were employed to the addition reactions and the asymmetric reactions were investigated. The ruthenium complex with BPPM or BINAP did not exhibited a catalytic effect, however, the ruthenium complex with DIOP catalyzed the reaction to give 1:1 adducts in high yield. The optical yields were determined to be 30%. It is very interesting that asymmetric induction was observed in the radical reactions in the coordination sphere since which is the first example. The reactions of methanesulfonyl chloride, trichloromethanesulfonyl chloride and carbon tetrachloride with olefin catalyzed <Ru_2> <Cl_4> <[(+) or (-)-DIOP]_3> were also investigated.
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