The chemistry and catalytic activity of new cationic ruthenium(II) complexes in the hydrogenation of cyclohexene. Crystal structure of [RuH(CO)(PPh 3)(P(OMe) 3)(Ph 2PCH 2CH 2AsPh 2)]ClO 4·n−C 5H 12

Abstract

Interaction of neutral ruthenium(II) complexes of the type [RuHCl(CO)(PPh 3) (L-L′)] [where L-L′ = Ph 2 PCH 2 CH 2 PPh 2 (dppe), 1; Ph 2PCH 2CH 2CH 2PPh 2 (dppp), 2; Ph 2PCH 2CH 2AsPh 2 (arphos), 3] with AgClO 4 in the presence of L″ [L″ = P(OMe) 3 or PME 3] yielded the new cationic ruthenium(II) complexes [RuH(CO)(PPh 3)(L″)(L-L′)]ClO 4 [where L-L′ = dppe, 4; dppp, 5 arphos, 6; L″ = PMe 3, 4; P(OMe) 3, 5 and 6]. All the complexes have been characterized by both analytical and spectroscopic (IR and 1H NMR) methods. The structure of a cationic complex 6, [RuH(CO)(PPh 3)(P(OMe) 3) (arphos)]ClO 4·n−C 5H 12, has been confirmed by single-crystal X-ray diffraction. The Ru atom is octahedrally coordinated with CO, PPh 3, and arphos in the equatorial plane and H and P(OMe) 3 in the axial positions. In the hydrogenation of cyclohexene, some relations between structures and catalytic activities have been studied. The cationic complexes have shown lower catalytic activities than their neutral analogues.