Synthesis and characterisation of [(η 6-cymene)Ru(L)X 2] compounds: single crystal X-ray structure of [(η 6-cymene)Ru(P{OPh} 3)Cl 2] at 203 K

Abstract

Treatment of the chloro bridged dimer {[(η 6-cymene)RuCl] 2(μ-Cl) 2} ( 1) with the donor molecules P(OPh) 3, P(OMe) 3, PPh 3, PMe 3, CO, SMe 2, CN t Bu and CNTos in hot hexane causes bridge splitting reactions that produce the monomeric compounds [(η 6-cymene)Ru(L)Cl 2], ( 4)–( 11), respectively. Use of the chiral isonitrile S(−)-α-methylbenzylisonitrile produced the corresponding complex 12. The diiodo analogues, 13– 15, were prepared similarly from {[(η 6-cymene)RuI] 2(μ-I) 2} ( 3) for P(OPh) 3, P(OMe) 3 and PPh 3, respectively. Insertion of tin(II) chloride into both metal–chlorine bonds was observed for [(η 6-cymene)Ru(P{OMe} 3)Cl 2] ( 5), while only monosubstitution was observed for [(η 6-cymene)Ru(PPh 3)Cl 2] ( 6). Halide abstraction in the presence of a substrate reaction has been used to prepare some selected cationic compounds which contain an asymmetric ligand environment. Reaction of {[(η 6-cymene)RuCl] 2(μ-Cl) 2} with 1,2-bis(diphenylphosphino)-ethane under ionising conditions produced the cation [(η 6-cymene)Ru(dppe)Cl]PF 6 ( 20). Selected compounds have been examined by { 13C– 1H} heteronuclear correlation and { 1H– 1H} COSY and NOESY experiments. The structure of [(η 6-cymene)Ru(P{OPh} 3)Cl 2] · CH 2Cl 2 ( 4) has been determined at −70 °C.