A ruthenium <i>cis</i>-dihydride with 2-phosphinophosphinine ligands catalyses the acceptorless dehydrogenation of benzyl alcohol

“…Recent developments have focused on the use of phosphinines as ligands [5][6][7][8][9][10], particularly in homogeneous catalysis [11][12][13][14][15] where they show interesting differences to conventional phosphine ligands. Examples from our group include the use of phosphinophosphinine complexes as small bite-angle ligands [16] for Ru-catalysed transfer hydrogenation, alcohol upgrading and acceptorless dehydrogenation reactions [17,18] as well as Cr catalysts for ethylene oligomerisation reactions producing unusual alkyl-and alkenylcyclopentane products [19] and Rh complexes for the hydroboration of carbonyls [20]. Others researchers have demonstrated the exceptional behaviour of Rh-phosphinine complexes in hydroformylation [21,22] and hydrogenation reactions [23], Au-phosphinine catalysts for cycloisomerisations [24] and cyclometalated iridium(III)phosphinine precatalysts for water oxidation reactions [25] among many others [5,11].…”

Section: Introductionmentioning

confidence: 99%

Reactivity Studies of Phosphinines: The Selenation of Diphenyl-Phosphine Substituents and Formation of a Chelating Bis(Phosphinine) Palladium(II) Complex

et al. 2022

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Phosphinines and donor-substituted phosphinines are of recent interest due to their use in homogeneous catalysis. In this article, a Pd(II) bis(phosphinine) complex was characterised and phosphorus–selenium coupling constants were used to assess the donor properties of the diphenylphosphine substituents of phosphinine ligands to promote their further use in catalysis. The selenation of 2,5-bis(diphenylphosphino)-3,6-dimethylphosphinine (5) and 2-diphenylphosphino-3-methyl-6-trimethylsilylphosphinine (6) gave the corresponding phosphine selenides 8 and 9, respectively, leaving the phosphinine ring intact. Multinuclear NMR spectroscopy, mass spectrometry and single crystal X-ray diffraction confirmed the oxidation of all the diphenylphosphine substituents with 1JP-Se coupling constants determined to be similar to SePPh3, indicating that the phosphinine rings were electronically similar to phenyl substituents. Solutions of 6 were found to react with oxygen slowly to produce the phosphine oxide 10 along with other by-products. The reaction of [bis{3-methyl-6-(trimethylsilyl)phosphinine-2-yl}dimethylsilane] (4) with [PdCl2(COD)] gave the chelating dichloropalladium(II) complex, as determined by multinuclear NMR spectroscopy, mass spectrometry and an elemental analysis. The molecular structure of the intermediate 2 in the formation of 4,6-di(tert-butyl)-1,3,2-diazaphosphinine (3) was also determined, which confirmed the structure of the diazaphosphacycle P(Cl){N=C(tBu)CH=C(tBu)-N(H)}.

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Activation of H–H, HO–H, C(sp²)–H, C(sp³)–H, and RO–H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples

et al. 2022

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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...

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A ruthenium cis-dihydride with 2-phosphinophosphinine ligands catalyses the acceptorless dehydrogenation of benzyl alcohol

Abstract: The first ruthenium dihydride stabilised with phosphinine ligands is described. Formed in situ, it was shown to catalyse the acceptorless dehydrogenation (AD) of benzyl alcohol to benzyl benzoate.

Cited by 4 publications

References 60 publications

Diphosphene with a phosphineborane tether and its rhodium complex

Diphosphene with a phosphineborane tether and its rhodium complex

Reactivity Studies of Phosphinines: The Selenation of Diphenyl-Phosphine Substituents and Formation of a Chelating Bis(Phosphinine) Palladium(II) Complex

Activation of H–H, HO–H, C(sp²)–H, C(sp³)–H, and RO–H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples

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A ruthenium cis-dihydride with 2-phosphinophosphinine ligands catalyses the acceptorless dehydrogenation of benzyl alcohol

Abstract: The first ruthenium dihydride stabilised with phosphinine ligands is described. Formed in situ, it was shown to catalyse the acceptorless dehydrogenation (AD) of benzyl alcohol to benzyl benzoate.

Cited by 4 publications

References 60 publications

Diphosphene with a phosphineborane tether and its rhodium complex

Diphosphene with a phosphineborane tether and its rhodium complex

Reactivity Studies of Phosphinines: The Selenation of Diphenyl-Phosphine Substituents and Formation of a Chelating Bis(Phosphinine) Palladium(II) Complex

Activation of H–H, HO–H, C(sp2)–H, C(sp3)–H, and RO–H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples

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Activation of H–H, HO–H, C(sp²)–H, C(sp³)–H, and RO–H Bonds by Transition-Metal Frustrated Lewis Pairs Based on M/N (M = Rh, Ir) Couples