Ruthenium(II) and ruthenium(IV) complexes containing κ1-P-, κ2-P,O-, and κ3-P,N,O-iminophosphorane-phosphine ligands Ph2PCH2P{=NP(=O)(OR)2}Ph2 (R = Et, Ph):: Synthesis, reactivity, theoretical studies, and catalytic activity in transfer hydrogenation of cyclohexanone

[{Ru(eta(6)-p-cymene)(mu-Cl)Cl}(2)] and [{Ru(eta(3):eta(3)-C10H16)(mu-Cl)Cl}(2)] react with Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2 (R = Et (1a), Ph (1b)) affording complexes [Ru(eta(6)-p-cymene)Cl-2(eta(6)-p-cymene)Cl-2(kappa(1)-Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2)] (R = Et (2a), Ph (2b)) and [Ru(eta(3):eta(3)-C10H16)Cl-2(kappa(1)-P-Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2)] (R = Et (6a), Ph (6b)). While treatment of 2a with 1 equiv of AgSbF6 yields a mixture of [Ru(eta(6)-p-cymene)Cl(kappa(2)-P,O-Ph2PCH2P{=NP(=O)(OEt)(2)}Ph-2)]-[SbF6] (3a) and [Ru(eta(6)-p-cymene)Cl(kappa(2)-P,N-Ph2PCH2P{=NP(=O)(OEt)(2)}Ph-2)][SbF6] (4a), [Ru(eta(6)-p-cymene)Cl(kappa(2)- P,O-Ph2PCH2P {=NP(=O)(OPh)(2)}Ph-2)][SbF6] (3b) and [Ru(eta(3):eta(3)-C10H16)Cl(kappa(3)-P,N,O-Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2)][SbF6](2) (R = Et (7a), Ph (7b)) are selectively formed from 2b and 6a,b. Complexes [Ru(eta(6)-p-cymene)(kappa(3)-P,N,O-Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2)][SbF6](2) (R = Et (5a), Ph (5b)) and [Ru(eta(3):eta(3)-C10H16)(kappa(3)-P,N,O-Ph(2)PCH2P{= NP(=O)(OR)(2)}Ph-2)][SbF6](2) (R = Et (8a), Ph (8b)) have been prepared using 2 equiv of AgSbF6. The reactivity of 3-5a,b has been explored allowing the synthesis of [Ru(eta(6)-p-cymene)X-2(kappa(1)-P-Ph2PCH2P{=NP(=O)(OR)(2)}Ph-2)] (R = Et, Ph; X = Br, I, N-3, NCO (9-12a,b)). The catalytic activity of 2-8a,b in transfer hydrogenation of cyclohexanone, as well as theoretical calculations on the models [Ru(eta6-C6H6)Cl(kappa(2)-P,N-H2PCH2P{=NP(=O).(OH)(2)}H-2)](+) and [Ru(eta(6)-C6H6)Cl(kappa(2)-P,O-H2PCH2P{=NP(=O)(OH)(2)}H-2)](+), has been also studied.