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Titolo:
SULFUR-HYDROGEN AND SELENIUM-HYDROGEN BOND ACTIVATION BY BOTH METAL CENTERS IN [MM'(CO)3(PH2PCH2PPH2)2] (M,M'=RH,IR)
Autore:
MCDONALD R; COWIE M;
Indirizzi:
UNIV ALBERTA,DEPT CHEM EDMONTON T6G 2G2 ALBERTA CANADA UNIV ALBERTA,DEPT CHEM EDMONTON T6G 2G2 ALBERTA CANADA
Titolo Testata:
Inorganic chemistry
fascicolo: 9, volume: 32, anno: 1993,
pagine: 1671 - 1680
SICI:
0020-1669(1993)32:9<1671:SASBAB>2.0.ZU;2-U
Fonte:
ISI
Lingua:
ENG
Soggetto:
MOLECULAR A-FRAMES; X-RAY STRUCTURE; DINUCLEAR PALLADIUM(I) COMPLEXES; BINUCLEAR CATIONIC COMPLEXES; MU-SILYLENE COMPLEXES; OXIDATIVE-ADDITION; RHODIUM COMPLEXES; IRIDIUM(I) COMPLEXES; SELECTIVE HYDROFORMYLATION; CATALYST PRECURSORS;
Tipo documento:
Review
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
112
Recensione:
Indirizzi per estratti:
Citazione:
R. Mcdonald e M. Cowie, "SULFUR-HYDROGEN AND SELENIUM-HYDROGEN BOND ACTIVATION BY BOTH METAL CENTERS IN [MM'(CO)3(PH2PCH2PPH2)2] (M,M'=RH,IR)", Inorganic chemistry, 32(9), 1993, pp. 1671-1680

Abstract

The complexes [M2(CO)3(dppm)2] (M = Rh (1), Ir (2); dppm = Ph2PCH2PPh2) react with H2S to produce [M2(CO)2(mu-S)(dppm)2], CO, and H-2; the reaction is immediate and quantitative for M = Rh, while for M = Ir a number of hydridic intermediates of general formula [Ir2(H)2(CO)2(mu-S)(dppm)2] are observed, allowing a mechanism for H2S addition and H-2 elimination to be proposed. Reaction of H2Se with 1 leads to several unidentified products, while with 2 hydridic products analogous to those observed in the H2S reaction are among those formed. The reactions of [RhIr(CO)3(dppm)2] (3) with H2S and H2Se yield [RhIr(H)(CO)2(mu-XH)(dppm)2] (X = S (7), Se (8)), which are proposed to have structures modeling the species formed by the first S-H bond addition to 1 or 2; these undergo no further rearrangement or elimination of H-2. Reactions of the thiols or selenols RXH (X = S, R = Et, Ph; X = Se, R = Ph) with 1 or 3 do not yield characterizable products; however with 2, complexes of the form [Ir2(XR)2(CO)2(mu-CO)(dppm)2] are obtained. One of these, [Ir2(SPh)2(CO)2(mu-CO)(dppm)2] (17), has been characterized by X-raycrystallography and is shown to have the SPh ligands disposed on one side of the Ir2P4 plane, while the one bridging and two terminal CO ligands are found on the opposite side. Complex 17 crystallizes with 1/2equiv of dichloromethane solvent in the monoclinic space group C2/c with a = 19.532(7) angstrom, b = 22.030(6) angstrom, c = 14.333(6) angstrom, beta = 102.82(4)-degrees, V = 6014(7) angstrom3, and Z = 4. On the basis of 3319 unique observations and 349 parameters varied, the structure has been refined to R = 0.040 and R. = 0.053. Although, in contrast to the reactions of 2 with H2S and H2Se, net loss of CO does notoccur in the formation of the dithiolate and diselenolate products, monitoring the reactions of 2 with RSH through use of variable-temperature multinuclear NMR spectroscopy indicates that dicarbonyl species such as [Ir2(H)2(SR)2(CO)2(dppM)2] are intermediates.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 01/12/20 alle ore 10:24:34