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排序方式: 共有179条查询结果,搜索用时 31 毫秒
1.
Rhodium catalysts have been prepared on palygorskite and montmorillonite (clay) supports by reduction with hydrogen (1 atmosphere) at room temperature of a cationic organometallic rhodium compound anchored to the support. The activity of these catalysts for the hydrogenation of liquid-phase 1-hexene remains constant with increase of prehydrogenation time and with re-use for several runs. No rhodium leaching is observed. 相似文献
2.
Xinyu Chen Yoshiro Oro Kenta Tanaka Norimichi Takenaka Hiroshi Bandow 《Analytical sciences》2004,20(7):1019-1023
A new stripping coil for the collection of nitrogen dioxide (NO2) has been developed to increase its versatility and efficiency. Nitrogen dioxide measurements based on quantitative collection through a reaction coil into an alkaline solution has been examined. Nitrogen dioxide is collected in a 0.1 N NaOH solution. This collection system has an efficiency of nearly 100%. The absorbed nitrogen dioxide has been measured by fluorescence detection with sub-ppbv detection limits. The excitation wavelength at 360 nm and the produced emission wavelength at 405 nm were suitable for nitrite ion measurements. 相似文献
3.
R. Usón L.A. Oro R. Sariego M. Valderrama C. Rebullida 《Journal of organometallic chemistry》1980,197(1):87-93
The preparation and properties of twenty five new cationic rhodium(I) complexes with tetrafluorobenzobarrelene and mono- or bidentate nitrogen or phosphorus donor ligands are described. The complexes with tertiary phosphines show high selectivities in the hydrogenation of 1-hexyne and several diolefins towards monoolefins. The dependence of the reduction rate upon the basicity of the phosphine has been studied. 相似文献
4.
Rafael Usón Pascual Lahuerta Daniel Carmona Luis A. Oro 《Transition Metal Chemistry》1980,5(1):327-329
Summary The preparation of the covalent Rh(OCIO3)(CS)(PCy3)2 and Rh(OClO3)(CS)(PPh3)(PCy3) perchlorato complexes is described, These complexes react with mono- or bidentate nitrogen donor ligands to give new cationic complexes of the [Rh(CS)(PCY3)2L]ClO4 and [Rh(CS)(PPh,)(PCy3)L]ClO4 types, 相似文献
5.
Carmona D Lahoz FJ Atencio R Edwards AJ Oro LA Lamata MP Esteban M Trofimenko S 《Inorganic chemistry》1996,35(9):2549-2557
Treatment of the metallo ligands [ML(pz)(2)(Hpz)] (pz = pyrazolate; L = C(5)Me(5), M = Ir (1); L = mesitylene, M = Ru (3)) with [M'Cl{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (4), Ni (5)) yields heterodinuclear complexes of formula [LM(&mgr;-pz)(2)(&mgr;-Cl)M'{HB(3-i-Pr-4-Br-pz)(3)}] (L = C(5)Me(5); M = Ir; M' = Co (6), Ni (7). L = mesitylene; M = Ru; M' = Co (8)). The related complex [Ru(eta(6)-p-cymene)(pz)(2)(Hpz)] (2) reacts with equimolar amounts of 4 or 5 to give mixtures of the corresponding bis(&mgr;-pyrazolato) &mgr;-chloro complexes [(eta(6)-p-cymene)Ru(&mgr;-pz)(2)(&mgr;-Cl)M'{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (9), Ni (10)) and the triply pyrazolato-bridged complexes [(eta(6)-p-cymene)Ru(&mgr;-pz)(3)M'{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (11), Ni (12)). Complex 1 reacts with 5 in the presence of KOH to give the IrNi complex [(eta(5)-C(5)Me(5))Ir(&mgr;-pz)(3)Ni{HB(3-i-Pr-4-Br-pz)(3)}] (13) whereas its reaction with 4 and KOH rendered the bis(&mgr;-pyrazolato) &mgr;-hydroxo complex [(eta(5)-C(5)Me(5))Ir(&mgr;-pz)(2)(&mgr;-OH)Co{HB(3-i-Pr-4-Br-pz)(3)}] (14). The molecular structure of the heterobridged IrCo complex (6) and those of the homobridged RuNi (12) and IrNi (13) complexes have been determined by X-ray analyses. Compound 6 crystallizes in the monoclinic space group P2(1)/n, with a = 10.146(5) ?, b = 18.435(4) ?, c = 22.187(13) ?, beta = 97.28(4) degrees, and Z = 4. Complex 12 is monoclinic, space group P2(1), with a = 10.1169(7) ?, b = 21.692(2) ?, c = 11.419(1) ?, beta = 112.179(7) degrees, and Z = 2. Compound 13 crystallizes in the monoclinic space group Cc, with a = 13.695(2) ?, b = 27.929(6) ?, c = 13.329(2) ?, beta = 94.11(4) degrees, and Z = 4. All the neutral complexes 6, 12, and 13 consist of linear M.M'.B backbones with two (6) or three (12, 13) pyrazolate ligands bridging the dimetallic M.M' units and three substituted 3-i-Pr-4-Br-pz groups joining M' to the boron atoms. The presence in the proximity of the first-row metal M' of the three space-demanding isopropyl substituents of the pyrazolate groups induces a significant trigonal distortion of the octahedral symmetry, yielding clearly different M'-N bond distances on both sides of the ideal octahedral coordination sphere of these metals. 相似文献
6.
Cationic rhodium(I) complexes of the general formula [Rh(COD)L2]ClO4 (L2 = bipyO2, phenO, dpeO2 and dpmO2) are prepared from the solvated species [Rh(COD)(Me2CO)x]+ and the appropriate ligand. Complexes of the type [Rhn(COD)n](ClO4)n (CNPyO = 4-cyano and 2-cyanopyridine N-oxide) are obtained similarly. Reaction of [RhCl(COD)]2 with the potassium salt of 2-picolinic acid N-oxide leads to the neutral complex Rh(COOPyO)(COD). The mononuclear rhodium diolefinic compounds react with carbon monoxide to give complexes of the type [Rh(CO)2L2]ClO4 and Rh(COOPyO)(CO)2, which on treatment with triphenylphosphine yield monocarbonyl derivatives.The catalytic activities of the diolefin complexes and related derivatives in hydrogen-transfer catalytic reactions have been studied. 相似文献
7.
Azulene as a ligand in cationic rhodium and iridium complexes. Crystal structure of [Rh(TFB)(az)]PF6
L.A. Oro M. Valderrama P. Cifuentes C. Foces-Foces F.H. Cano 《Journal of organometallic chemistry》1984,276(1):67-77
Rhodium or iridium complexes of formula [M(diolefin)(az)]+ have been prepared by treating [MCl(diolefin)]2 complexes with silver salts and azulene, and also by treating [Rh(diolefin)2]+ with azulene. The reactions of some representative complexes have been studied. Reaction of [M(C5Me5)(Me2CO)3]2+ with azulene appears to give dinuclear diazulene cationic complexes. The crystal structure of compound [Rh(TFB)(az)]PF6 has been solved by X-ray methods. It crystallizes in the space group P21/c with cell constants 8.4241(4), 16.6911(8), 15.0026(7) Å, 95.897(6)°. Refinement gave R = 0.027 and Rw = 0.032 for 2991 observed reflexions. The Rh atom is coordinated to the five-membered ring, with RhC distances shortest for the atoms which are trans to the diolefinic double bonds. The bonding scheme within the azulene ligand differs from that in the parent hydrocarbon. 相似文献
8.
The reaction of [Rh4(mu-PyS2)2(cod)4] (PyS2 = 2,6-pyridinedithiolate, cod = 1,5-cyclooctadiene) with CF3SO3Me gave the cationic complex [Rh(4)(mu-PyS(2)Me)(2)(cod)4][CF3SO3]2 (1) with two 6-(thiomethyl)pyridine-2-thiolate bridging ligands from the attack of Me+ at the terminal sulfur atoms of the starting material. Under identical conditions [Rh4(mu-PyS2)2(tfbb)4] (tfbb = tetrafluorobenzobarrelene) reacted with CF3SO3Me to give the mixed-ligand complex [Rh(4)(mu-PyS2)(mu-PyS2Me)(tfbb)4][CF3SO3] 2. The nucleophilicity of the bridging ligands in the complexes [Rh4(mu-PyS2)2(diolefin)4] was exploited to prepare heteropolynuclear species. Reactions with [Au(PPh3)(Me2CO)][ClO4] gave the hexanuclear complexes [(PPh3)2Au2Rh4(mu-PyS2)2(diolefin)4][ClO4]2 (diolefin = cod (3), tfbb (4)). The structure of 4, solved by X-ray diffraction methods, showed the coordination of the [Au(PPh3)]+ fragments to the peripheral sulfur atoms in [Rh4(mu-PyS2)2(diolefin)4] along with their interaction with the neighbor rhodium atoms. Neutral coordination polymers of formula [ClMRh4(mu-PyS2)2(diolefin)4]n (M = Cu (5, 6), Au (7)) result from the self-assembly of alternating [Rh4(mu-PyS2)2(diolefin)4] ([Rh4]) blocks and MCl linkers. The formation of the infinite polymetallic chains was found to be chiroselective for M = Cu; one particular chain contains exclusively homochiral [Rh4] complexes. Cationic heterometallic coordination polymers of formula [MRh4(mu-PyS2)2(diolefin)4]n[BF4]n (M = Ag (8, 9), Cu (10, 11)) and [Rh5(mu-PyS2)2(diolefin)5]n[BF4]n (12, 13) result from the reactions of [Rh4] with [Cu(CH2CN)4]BF4, AgBF4, and [Rh(diolefin)(Me2CO)2]BF4, respectively. The heterometallic coordination polymers exhibit a weak electric conductivity in the solid state in the range (1.2-2.8) x 10(-7) S cm(-1). 相似文献
9.
Cationic rhodium(I) norbornadiene complexes with polystyrene-immobilized imidazole, tetramethylbiimidazole or phosphine ligands in the presence of potassium hydroxide catalyze hydrogen transfer from isopropanol to acetophenone and 1-hexene. [Rh(NBD) (poly-PPh2)2] ClO4 complexes are particularly efficient for the reduction of acetophenone, but slow decomposition to rhodium metal is observed.
(I) , , , 1-. [Rh(NBD) (-PPh2)2]ClO4 , .相似文献
10.
Summary The preparations and characterisation of cationic complexes of the type [Rh(CO)(MeCN)(PR3)2]ClO4, [Rh(CO)L(PR3)2]ClO4 (L=py or 2-MeOpy), [Rh(CO)(L-L)(PR3)2]ClO4 (L-L = bipy or phen) and [Rh(CO)(PR3)3]ClO4 with PR3 = P(p-YC6H4)3 (Y=Cl, F, Me or MeO) are described. 相似文献