Octahedral ruthenium(II) complexes cis, cis-[RuX 2(CNR)(CO)(P ∧P)] and cis, cis, cis-[RuX 2(CO) 2(P ∧P)] (X = Cl, Br; P ∧P = 1,1′-bis(diphenylphosphino)ferrocene, 1,1′-bis(diisopropylphosphino)ferrocene): Synthesis and catalytic applications in transfer hydrogenation of acetophenone and cycloisomerization of ( Z)-3-methylpent-2-en-4-yn-1-ol

Abstract

Carbonyl–isocyanide-ruthenium(II) complexes cis, cis-[RuX 2(CNR)(CO)(P ∧P)] (P ∧P = dppf, dippf; X = Cl, Br; R = Bn, Cy, t Bu, 2,6-C 6H 3Me 2, ( S)-(−)-C(H)MePh) ( 3– 6a– e) have been prepared in high yields by treatment of the dimeric derivatives [{RuX(μ-X)(CO)(P ∧P)} 2] (P ∧P = dppf, dippf; X = Cl, Br) ( 1– 2a– b) with isocyanides. Dimers 1– 2a– b also react with carbon monoxide to afford the dicarbonyl species cis, cis, cis-[RuX 2(CO) 2(P ∧P)] ( 7– 8a– b). The catalytic activity of these compounds in transfer hydrogenation of acetophenone by propan-2-ol as well as in cycloisomerization of ( Z)-3-methylpent-2-en-4-yn-1-ol into 2,3-dimethylfuran has been studied.