Activation of H–H, HO–H, C(sp(2))–H, C(sp(3))–H, and RO–H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples

[Image: see text] Reaction of the dimers [(Cp*MCl)(2)(μ-Cl)(2)] (Cp* = η(5)-C(5)Me(5)) with Ph(2)PCH(2)CH(2)NC(NH(p-Tolyl))(2) (H(2)L) in the presence of NaSbF(6) affords the chlorido complexes [Cp*MCl(κ(2)N,P-H(2)L)][SbF(6)] (M = Rh, 1; Ir, 2). Upon treatment with aqueous NaOH, solutions of 1 and 2 yield the corresponding complexes [Cp*M(κ(3)N,N′,P-HL)][SbF(6)] (M = Rh, 3; Ir, 4) in which the ligand HL presents a fac κ(3)N,N′,P coordination mode. Treatment of THF solutions of complexes 3 and 4 with hydrogen gas, at room temperature, results in the formation of the metal hydrido-complexes [Cp*MH(κ(2)N,P-H(2)L)][SbF(6)] (M = Rh, 5; Ir, 6) in which the N(p-Tolyl) group has been protonated. Complexes 3 and 4 react with deuterated water in a reversible fashion resulting in the gradual deuteration of the Cp* group. Heating at 383 K THF/H(2)O solutions of the complexes 3 and 4 affords the orthometalated complexes [Cp*M(κ(3)C,N,P-H(2)L(-H))][SbF(6)] [M = Rh, 7; Ir, 8, H(2)L(-H) = Ph(2)PCH(2)CH(2)NC(NH(p-Tolyl))(NH(4-C(6)H(3)Me))], respectively. At 333 K, complexes 3 and 4 react in THF with methanol, primary alcohols, or 2-propanol giving the metal-hydrido complexes 5 and 6, respectively. The reaction involves the acceptorless dehydrogenation of the alcohols at a relatively low temperature, without the assistance of an external base. The new complexes have been characterized by the usual analytical and spectroscopic methods including the X-ray diffraction determination of the crystal structures of complexes 1–5, 7, and 8. Notably, the chlorido complexes 1 and 2 crystallize both as enantiopure conglomerates and as racemates. Reaction mechanisms are proposed based on stoichiometric reactions, nuclear magnetic resonance studies, and X-ray crystallography as well as density functional theory calculations.