32240-58-7Relevant academic research and scientific papers
The dehydrogenation of ammonia-borane catalysed by dicarbonylruthenacyclic(II) complexes
Boulho, Cedric,Djukic, Jean-Pierre
, p. 8893 - 8905 (2011/01/06)
The reactivity of ruthenacyclic compounds towards ammonia-borane's dehydrogenation was investigated by considering both hydrolytic and anhydrous conditions. The study shows that the highly soluble μ-chlorido dicarbonylruthenium(II) dimeric complex derived from 4-tert-butyl,2-(p-tolyl) pyridine promotes, with an activation energy Ea of 22.8 kcal mol -1, the complete hydrolytic dehydrogenation of NH3BH 3 within minutes at ca. 40 °C. The release of 3 eq. of H 2 entails the formation of boric acid derivatives and the partly reversible protonolysis of the catalyst, which produces free 2-arylpyridine ligand and a series of isomers of Ru(CO)2(H)(Cl) . Under anhydrous conditions, hydrogen gas release was found to be slower and the dehydrogenation of NH3BH3 results in the formation of conventional amino-borane derivatives with concomitant protonolysis of the catalyst and release of isomers of Ru(CO)2(H)(Cl) . The mechanism of the protonolysis of the ruthenacycle was investigated with state-of-the-art DFT-D methods. It was found to proceed by the concerted direct attack of the catalyst by NH3BH3 leading either to the formation of a coordinatively unsaturated Ru(CO)2(H)(Cl) species. The key role of Ru(CO)2(H)(Cl) species in the dehydrogenation of ammonia-borane was established by trapping and quenching experiments and inferred from a comparison of the catalytic activity of a series of dicarbonylruthenium(II) complexes. The Royal Society of Chemistry 2010.
Intramolecular protonation and other mechanisms for substitution reactions of hydrido(thiolato)-and di(thiolato)-ruthenium(II) phosphine complexes
Jessop, Philip G.,James, Brian R.
, p. 75 - 86 (2008/10/08)
Reactions of cct-RuH(SR) (CO)2(PPh3)2 (1) (cct=cis, cis, trans) with R'SH provide cct-RuH(SR′)(CO)2(PPh3)2 (R = alkyl, aryl); based on described kinetic data, the proposed mechanism involves PPh3 loss, coordination of R′SH, intramolecular protonation of RS- by R′SH, and RSH elimination. The intramolecular protonation step circumvents a potentially slow RSH reductive elimination step. A similar mechanism is proposed for the thiol exchange reactions of cct-Ru(SR)2(CO)2(PPh3)2 (2). A corresponding dissociative mechanism is also proposed for the reaction of 1 with P(p-tolyl)3, which gives cct-RuH(SR)(CO)2(PPh3)(P(p-tolyl)3) and cct-RuH(SR)(CO)2-(P(p-tolyl)3)2. Other reactions described include the reactions of 1 with H2, CO, HCl and PPh3, and the reactions of 2 with P(p-tolyl)3 and H2. Exposure to light causes 2 to dimerize in solution.
New Ruthenium-Molybdenum and -Tungsten Heterodinuclear Complexes with trans-Styryl Ligand
Fukuoka, Atsushi,Ohashi, Nobutoshi,Komiya, Sanshiro
, p. 69 - 72 (2007/10/02)
New styryl ruthenium-molybdenum and -tungsten complexes Cp(CO)3M-Ru (trans-styryl)(CO)(PPh3)2 have been prepared by the metathetical reactions of Ru(trans-styryl)Cl(CO)(PPh3)2 with Na.The reactions of 2 with CO and with PMe3
Reactions of acyl(carbonyl)ruthenium(II) and acyl(carbonyl)iron(II) complexes with amines. Preparation of novel propionyl(carbamoyl)ruthenium(II) complexes
Ozawa, Fumiyuki,Chikaoka, Satoyuki,Cao, Xi-Zhang,Yamamoto, Akio
, p. 173 - 183 (2007/10/02)
Treatment of Ru(COEt)Cl(CO)(PPh3)2 (1) with secondary amines (R2NH) under pressure of CO and/or ethylene gives propionyl-carbamoyl complexes Ru(COEt)(CONR2)(CO)(PPh3)2 (NR2 = NEt2 (4a), N(CH2)4CH2 (4b), NMe2 (4c)) together with the ammonium salt R2NH2Cl.Complexes 4a-c have been isolated as pale yellow crystals and characterized by means of NMR and IR spectroscopy and elemental analysis.Reactions of Fe(COMe)I(CO)2(PMe3)2 and BF4 with nucleophiles (HNEt2, LiNMe2, EtOH (in conjunction with Et3N) and NaOMe) give the corresponding acetamides and acetic acid esters.
Hydrido thiolato and thiolato complexes of ruthenium(II) carbonyl phosphines
Jessop, Philip G.,Rettig, Steven J.,Lee, Chung-Li,James, Brian R.
, p. 4617 - 4627 (2008/10/08)
Oxidative addition of RSH (R = H, alkyl, aryl) or RSSR (R = aryl) to Ru(CO)2L3 (L = PPh3, 1) yields respectively cct-RuH(SR)(CO)2L2 (type 2) (cct = cis,cis,trans) or cct-Ru(SR)2(CO)2L2 (type 3); a hydrido selenolate species is made similarly using PhSeH. Methods for in situ formation of corresponding mixed bis(thiolate) species are also given. 1 is generally unreactive toward thioethers, although with propylene sulfide cct-Ru(η2-S2) (CO)2L2 is produced. Metathesis reactions of cct-RuCl2(CO)2L2 with NaSR salts yield 3 (R = aryl) or, when R = Et, cct-RuCl(SEt)(CO)2L2 or [L(CO)2Ru(μ2 -SEt)2(μ3-SEt)Na(THF)]2 (4), depending on reaction conditions. The complexes are characterized by IR spectroscopy, 1H, 31P, and, in some cases, 13C NMR spectroscopy, and for 2g and 3g (R = SC6H4pMe) and 4, X-ray crystallography. All three complexes crystallized in the space group P1. For 2g, a = 12.340 (4) A?, b = 14.948 (3) A?, c = 10.684 (4) A?, α = 90.05 (3)°, β = 99.27 (3)°, γ = 86.84 (3)°, V = 1942 (1) A?3, and Z = 2; the structure refined to R = 0.032 and Rw = 0.037 for 7174 reflections with Fo2 > 3σ(Fo2). Corresponding crystallographic data for 3g are a = 13.173 (3) A?, b = 19.766 (4) A?, c = 9.770 (4) A?, α = 98.26 (2)°, β = 91.24 (3)°, γ = 78.31 (2)°, V = 2465 (1) A?3, Z = 2, R = 0.041, and Rw = 0.043 for 3597 reflections; for 4, a = 12.189 (3) A?, b = 13.124 (3) A?, c = 12.032 (4) A?, α = 99.70 (2)°, β = 110.61 (2)°, γ = 67.95 (2)°, V = 1668.4 (8) A?3, Z = 1, R = 0.039, and Rw = 0.043 for 4252 reflections. 4 has an unprecedented network of transition-metal and alkali-metal ions bridged by thiolate ligands: four thiolates bridge one Ru and one Na, and two thiolates bridge one Ru and two Na atoms. The geometries at Ru and Na are close to octahedral and square pyramidal, respectively. Trends are noted for the 1H NMR shifts and 2JPH values for the hydride in 2, and an additivity rule formulated for the 31P shift within the cct-Ru(SR)(SR′)(CO)2(PPh3)2 species. Limited kinetic data suggest that the oxidative addition reactions to 1 probably proceed via a nonradical process, following dissociation of a PPh3 ligand.
Kinetics and mechanism of the hydrogenolysis of a ruthenium(II) acyl complex
Joshi,James
, p. 199 - 205 (2008/10/08)
The kinetics of the solution hydrogenolysis of the six-coordinate Ru(II) acyl complex RuCl(COR)(CO)2(PPh3)2, where R = norbornenyl, to give RuHCl(CO)2(PPh3)2 and RCHO reveal that the proces
Substituted ketene elimination from acid chlorides induced by ruthenium(0) compounds
Singh, Shanti,Baird, Michael C.
, p. 255 - 260 (2007/10/02)
The compound Ru(CO)2(triphos) (triphos=MeC(CH2PPh2)3) reacts with a number of acid chlorides RR'CHCOCl to form Cl and the corresponding substituted ketenes RR'CCO.A quantitative study of the reaction of Ph2CHCOCl shows that Ph2CCO is formed in a 1:1 stoichiometry.The compound Ru(CO)3(PPh3)2 also reacts with Ph2CHCOCl forming Ph2CCO and the unstable hydride Cl, the chemistry of which is also reported.
METATHETICAL REACTIONS OF CARBONYLATE ANIONS WITH DICHLORORUTHENIUM COMPLEXES: PREPARATION AND CHARACTERIZATION OF RUTHENIUM-MOLYBDENUM AND RUTHENIUM-MANGANESE COMPLEXES
Sabo, Sylviane,Chaudret, Bruno,Gervais, Daniele
, p. 411 - 418 (2007/10/02)
The possibility of making metal-metal bonded heterobimetallic species by metathesis of ruthenium dichlorides with anionic carbonylates is demonstrated by the isolation of MoRu(μ-Cl)(CO)2(PPh3)2(η-C5H5) (1) and MnRuCl(μ-CO)2(CO)3(μ-dppm)2 (2), obtained by action of - on RuCl2(PPh3)3 and of Mn(CO)5- on RuCl2(dppm)2, respectively.In contrast, reaction of Mn(CO5)- with RuCl2(PMe3)4 yielded an ionic species 3 containing the diruthenium cation Ru2Cl3(PMe3)46+.More interestingly, the action of Mn(CO)5- on RuCl2(PPh3)3 resulted in formation of the unexpected complex MnRu(μ-PPh2)(CO)6(PPh3)2 (4) in which the phosphido group PPh2 bridges the two metals; this process is shown to involve a hydride intermediate, and elimination of a molecule of benzene, both identified in the reaction mixture.
