Cooperative Bond Activation Reactions with Ruthenium Carbene Complex PhSO₂(Ph₂PNSiMe₃)C═Ru(p-cymene): Ru═C and N–Si Bond Reactivity

Abstract

The synthesis of ruthenium carbene complex PhSO 2 (Ph 2 PNSiMe 3 )CRu(p-cymene) (3) and its application in cooperative bond activation reactions were studied. Compound 3 is accessible via salt metathesis using the dilithium methandiide ligand or alternatively via dehydrohalogenation of the corresponding chlorido complex 2. The carbene complex was studied by Xray crystallography, multielement NMR spectroscopy, and DFT studies, all of which confirm the presence of a RuC double bond. The polarization of the RuC bond is less pronounced than in an analogous carbene complex with a thiophosphoryl instead of the iminophosphoryl moiety. This should be beneficial for realizing reversible activation processes by the addition of element-hydrogen bonds across the RuC double bond. Accordingly, 3 is more stable and the RuC linkage less reactive in the activation of aromatic alcohols and elemental dihydrogen, showing reversible processes and longer reaction times. Despite the selective addition of dihydrogen across the Ru− C bond, the activation of O−H bonds was accompanied by hydrolysis of the N−Si linkage. The reaction of 3 with water led to the hydrolysis of the N−Si bond as well as protonative cleavage of the central P−C bond in the ligand backbone, thus resulting in the formation of an unusual dinuclear ruthenium−imido complex. Article pubs.acs.org/Organometallics

Versatile Modes of Cooperative B−H Bond Activation Reactions in Ruthenium‐Carbene Complexes: Addition, Ring‐Opening and Insertion

“…[18] In contrast, PinBH only delivered B 2 pin 3 and the H 2 activation product previouslyr eported by our group. [19,20] Similar decomposition of PinBH has been observedb efore. [21] To explain the observed reactivities of 1a and 1b towards different boranes and to get insights into the reaction mechanisms computational studies on methyl-substituted model sys-Scheme2.Reactionofc omplex 1 with pinacolborane and BH 3 ·SMe 2 .…”

“…Thereby,s ingle-crystals of 3 were obtained in 66 %y ield by diffusion of pentane into at oluenes olution of the crude reaction mixture. 3 is characterized by two broad signals at d B = À16.8 and À21.0 ppm in the 11 B{ 1 H} NMR spectrum.A dditionally,t he 1 HNMR spectrum features ad oublet at d H = 2.88 ppm ( 2 J PH = 4.0 Hz), consistent with protonation of the former carbene carbon atom, as well (3),Ru ÀS1 2.4382(9), RuÀB 2.457(4), PÀS1 2.0140(11), S2ÀO1 1.440(2),S 2 ÀO2 1.447 (2),P ÀC1 1.780 (3), S2ÀC1 1.752 (3), C1-B-Ru 61.63(16), C1-Ru-S17 7.84 (8), S2-C1-P 120.44 (19), S2-C1-Ru 115.69 (17), B1-C1-Ru79.44 (19). 3:Ru ÀC1 2.189(4), RuÀS1 2.3872 (11), RuÀB2 .395(5),S1 ÀB2 1.903(5),S 1 ÀB1 1.942(5),S2 ÀO2 1.441 (3), S2ÀO1 1.456 (3), S2ÀC1 1.753(4), PÀC1 1.809(4),P 1 ÀB1 1.928(5), B2-S1-B1106.7(2), B2-S1-Ru 66.78 (15), S2-C1-P 122.0(2), S2-C1-Ru1 15.8 (2), P-C1-Ru 108.8 (2), P-B1-S1102.8 (2), S1-B2-Ru 66.33(16).…”

Geminal Dianions Stabilized by Main Group Elements

“…This is of major importance since it showed that the addition of O-H bond across the Ru=C proceeded via a low energy transition state. The same reactivity was studied with [Ru(17)(cymene)] 129. If the first addition of ArOH on the Ru=C bond led to analogous reactivity as for [Ru(11)(cymene)], the complex further…”

“…Similar results were reported in 2018 by the same group for the mixed PN/SO 2 dianion 17Li 2 in the synthesis of the [Ru(17)(cymene)] complex (scheme 63). Alternatively, the complex can be obtained from the monoanion coordination followed by deprotonation in the coordination sphere of Ru 129.…”

Cooperative Bond Activation Reactions with Nickel and Palladium Carbene Complexes with a PCcarbeneS Pincer Ligand

“…As in the case of the PCP complexes, also in these compounds, additional donor sites are used to increase the complex stability. For example, our group has used ruthenium carbene complexes of type B with two anion-stabilizing groups including a thiophosphoryl tether to stabilize nucleophilic ruthenium carbene species which were found to be applicable in a wide variety of bond activation reactions (H–H, O–H, Si–H, B–H, P–H).…”