F. Gordon

Metal framework arrangements in pentanuclear gold-ruthenium clusters. Crystal structures of [Au2Ru3(μ3-S)(CO)8(PPh3)3] and [Au2Ru3(μ-H)(μ3-COMe)(CO)9(PPh3)2]

Abstract Reaction between the compounds [AuMe(PPh3)] and [Ru3(μ-H)2(μ3-S)(CO)9] in toluene affords a mixture of products [AuRu3(μ-H)(μ3-S)(CO)8(PPh3)L] [Ru3(μ-H)2(μ3-S)(CO)7(PPh3)L], and Au2Ru3(μ3-S)(CO)8(PPh3)2L] (L = CO pr PPh3). The molecular structure of [Au2Ru3(μ3-S)(CO)8(PPh3)3] has been established by a single-crystal X-ray diffraction study. The Au2Ru3 metal atom core adopts a trigonal bipyramidal structure, with gold atoms occupying equatorial and apical sites. In contrast, in the species [Au2Ru3(μ-H)(μ3-COMe)(CO)9(PPh3)2], also studied by X-ray diffraction, the metal atoms have a distorted square pyramidal structure with a ruthenium atom at the apex. These structural studies allow interpretation of the dynamic behaviour of [Au2Ru3(μ3-S)(CO)8(PPh3)3], observed in solution by NMR measurements. It is proposed that facile AuRu bond rupture takes place to afford an intermediate with a square pyramidal Au2Ru3 core, as found in [Au2Ru3(μ-H)μ3-COMe)(CO)9(PPh3)2].

Fulvene—platinum complexes: X-ray crystal structure of [Pt(η2-C5H4CPh2)(PPh3)2]

Summary Bis(cycloocta-l,5-diene)platinum reacts with 2,3,4,5-tetraphenylfulvene to afford the complex [Pt( η 2 -CH 2 =C 5 Ph 4 )(cod)] (cod = C 8 H 12 ) in which the metal atom is coordinated to the exo -cyclic double bond of the fulvene. Related compounds [Pt( η 2 -CH 2 =C 5 Ph 4 )L 2 ] (L = PPh 3 , PMePh 2 , PMe 2 Ph, AsPh 3 or CNBu t ) have also been prepared and characterised. Reaction of the complexes [Pt-(C 2 H 4 ) 2 (L)] (L = P(cyclo-C 6 H 11 ) 3 , PPh 3 or AsPh 3 ) with 2,3,4,5-tetraphenylfulvene yields the compounds [Pt(C 2 H 4 )( η 2 -CH 2 =C 5 Ph 4 )(L)]. NMR data for the new species are reported and discussed. 6,6-Diphenylfulvene reacts with [Pt(cod) 2 ] and PPh 3 (1/2 mol ratio) to give the complex [Pt( η 2 -C 5 H 4 CPh 2 )-(PPh 3 ) 2 ] in which the metal atom is bonded to carbon atoms C(2) and C(3) of the fulvene ring. This was established by an X-ray diffraction study. Crystals are monoclinic, space group P2 1 / n , with Z = 4 in a unit cell of dimensions a = 13.761(4), b = 21.653(13), c = 17.395(6) A, β = 104.46(2)°. The structure has been solved and refined to R = 0.064 ( R ′ = 0.064) for 3139 independent diffracted intensities measured at room temperature. The platinum atom is in a trigonal environment formed by the two ligated phosphorus atoms and the C−C bond of the fulvene which is elongated to 1.52(3) A. The C 5 fulvene ring is planar, and makes an angle of 108° with the coordination plane around the platinum. In this plane the metal atom is slightly asymmetrically bonded with Pt−C 2.15(2) and 2.24(2) A, and Pt−P 2.280(6) and 2.301(6) A.

Synthesis of alkylidyne tungsten complexes with hydrotris(pyrazol-1-yl)borate ligands

Abstract Treatment of the tungsten compounds [W(CR)Br(CO) 4 ] (R = C 6 H 4 Me-4, C 6 H 4 OMe-2, or C 6 H 3 Me 2 -2,6) in tetrahydrofuran with the salts K[HB(3,5-Me 2 pz) 3 ][HB(3,5- Me 2 pz) 3 = hydrotris(3,5-dimethylpyrazol-1-yl)borate], K[HB(3-Phpz) 3 ] [HB(3-Phpz) 3 = hydrotris(3-phenylpyrazol-1-yl)borate] and K[HB(pz) 3 ] [HB(pz) 3 = hydrotris(pyrazol-1-yl) borate], affords, respectively, the complexes [W(CC 6 H 4 Me-4)(CO) 2 {HB(3,5-Me 2 pz) 3 }], [W(C 6 H 4 Me-4)(CO) 2 {HB(3-Phpz) 3 }] and [W(CR)(CO) 2 {HB(pz)3}] (R = C 6 H 3 Me 2 -2,6 or C 6 H 4 OMe-2). Protonation of the compound [W(CC 6 H 4 OMe-2)(CO) 2 {HB(pz) 3 }] with HBF 4 ·Et 2 O gives the salt [W{C(H) C 6 H 4 OMe-2}(CO) 2 {HB(pz) 3 }][BF 4 ]. The NMR data for the new complexes are reported and discussed.

The crystal structure of [Rh3(μ3-CO)2(η-C5Me5)3] and reactions of the unsaturated metal clusters [MM′2(μ3-CO)2(η-C5Me5)3] (M = M′ = Rh; M = Co or Ir, M′ = Rh) with hydrogen☆

Abstract An X-ray crystallographic study of the complex [Rh3(μ3-CO)2(η-C5Me5)3] has revealed that the CO ligands asymmetrically bridge the Rh3 triangle in accord with theoretical predictions. Treatment of the trirhodium compound, or the related mixed-metal complexes [MRh2-(μ3-CO)2(η-C5Me5)3] (M = Co or Ir), with hydrogen gas gives the species [MRh2(μ-H)2(μ-CO)(μ3-CO)(η-C5Me5)3]; the molecular structure of the dihydridotrirhodium cluster has been established by X-ray diffraction.

Hydride addition and related reactions of cyclo-octa-1,5-diene(tetra-carbonyl) manganese(I)

Abstract The cations [M(CO) 4 (cod)] + (M = Mn or Re; cod = cyclo-octa-1,5-diene) have been isolated as their tetraflouroborate salts. The manganese compound reacts with sodium tetrahydroborate to afford initially (1,4-5-η-cyclo-octenyl) (tetracarbonyl)manganese which isomerises to (1,3-η-cyclo-octenyl)(tetracarbonyl)manganese. Both complexes react with triphenylphosphine of trimethylphosphite to give the compounds [fac-Mn(CO) 3 (L)(1,4-5-η-C 8 H 13 )] (L = Ph 3 P or (MeO) 3 P). Reaction of [Mn(CO) 4 (cod)][BF 4 ] with methoxide, azide, cyanide or iodide ions and with 1,8-bis(dimethylamino)napthalene are also described.

Reaction of low-valent metal complexes with fluorocarbons. Part 30. Bis(cyclo-octa-1,5-diene)platinum with hexafluoroacetone, 1,1 -dicyano-2,2- bis(trifluoromethyl)ethylene and N-methylhexafluoroisopropylideneamine; crystal and molecular structures of [Pt2{(CF3)2CO}(1,5-C8H12)2] and [Pt·C(CF3)2·O·C(CF3)2O·(1,5-C8H12)]

Reaction of [Pt(1,5-C8H12)2] with hexafluoroacetone affords, depending on reaction conditions, the complexes [Pt2{(CF3)2CO}(1,5-C8H12)2], [P[graphic omitted](1,5-C8H12)], and [P[graphic omitted]H- 1,5-C8H12)] and [P[graphic omitted](1.5-C8H12)]. The structural identities of the first two complexes have been established by the analysis of single-crystal X-ray data. The dinuclear complex is monoclinic, space group P21/c with four molecules in a unit cell of dimensions a= 9.917(3), b= 14.957(6). c= 13.358(3)A; β= 102.18(2)°. The structure has been solved by conventional heavy-atom methods from 2 083 diffracted intensities and refined to R 0.038 (R′ 0.044). The molecule contains an approximate mirror plane formed by the two platinum atoms [Pt–Pt 2.585(1)A] and the carbon and oxygen atoms of the hexafluoroacetone molecule, with the cyclo-octa-1,5- diene molecules symmetrically bonded to each platinum atom in the tub configuration.Crystals of the second complex are triclinic, space group P with two molecules in a unit cell of dimensions a= 8.212(3), b= 9.329(2), c= 12.610(3)A: α= 91.87(2). β= 102.10(2). γ= 111.25(3)°. The structure has been solved from 2 659 diffracted intensities to R 0.029 (R′ 0.035) by conventional methods. The platinum atom forms part of a five-membered condensed (head-to-tail) ring P[graphic omitted], and is co-ordinated by a cyclo-octa- 1,5-diene molecule in a tub configuration. In both compounds the platinum atoms show essentially square-planar co-ordination.In a third complex the hexafluoroacetone forms part of a five-membered ring, in which it links the platinum and an olefin carbon atom of cycle-octa-1,5-diene. A similar complex, [P[graphic omitted]H(1,5-C8H12)], is a minor product from the reaction of [Pt(1,5-C8H12)2] with 1,1 -dicyano-2,2-bis(trifluroromethyl)ethylene. N-Methylhexafluoroisopropylideneamine and [Pt(1,5-C8H12)2] afford [P[graphic omitted]Me(1,5-C8H12)].

(Carbaborane)rhodium-copper and -manganese complexes. Crystal structure of [RhCu(PPh3)(cod)(η5-7,8-C2B9H9Me2)]

Abstract Treatment of [CuCl(PPh 3 )] with [NEt 4 ][Rh(cod)(η 5 -7,8-C 2 B 9 H 9 Me 2 )] (cod = cyclo-octa-1,5-diene) in CH 2 Cl 2 in the presence of TlBF 4 affords the dimetal compound [RhCu(PPh 3 )(cod)(η 5 -7,8-C 2 B 9 H 9 Me 2 )], the structure of which has been established by X-ray diffraction (RhCu 2.633(2) A, RhCuP 153.3(1)°). Reactions between [MnBr(CO) 5 ] and the tetraethylammonium salts of the complexes [Rh(CO)(PPh 3 )(η 5 -7,8-C 2 B 9 H 9 Me 2 )] - and [Rh(cod)(η 5 -7,8-C 2 B 9 H 9 Me 2 )] − yield the dimetal compounds [MnRh(CO) 5 (L)(η 5 -7,8-C 2 B 9 H 9 Me 2 )] (L=PPh 3 or CO) respectively. Treatment of [Mn(CO) 2 (NO)(η 5 -C 5 H 4 Me)][BF 4 ] with [NEt 4 ][Rh(CO)(PPh 3 )(η 5 -7,8-C 2 B 9 H 9 Me 2 )] affords [Rh(NO)(PPh 3 )(η 5 -7,8-C 2 B 9 H 9 Me 2 )], in an unusual reaction involving transfer of the NO ligand from manganese to rhodium.

Synthesis of complexes with tungstencobalt bonds via alkylidyne group coupling reactions; crystal structure of the compound [Wco{μ-C(C6H4Me-4)C(O)C(C6H4Me-4)}(CO)5(η-C5H5)]

Abstract Reactions between the comounds [WCo(CR)(CO) 8 ] and [W(CR)(CO) 2 (L)] (R = C 6 H 4 Me-4, L = η-C 5 H 5 or η-C 5 Me 5 ) afford chromatographically separable mixtures of the heterodinuclear compounds [WCo(μ-RC 2 R)(CO) 5 (L)] and [WCo{μ-C(R)C(O)C(R)}(CO) 5 (L)]. In contrast, the reaction between [Wco(CMe)(CO) 8 ] and [W(CMe)(CO) 2 (η-C 5 H 5 )] yields only the μ-alkyne complex [WCo(μ-MeC 2 Me)(CO) 5 (η-C 5 H 5 )], while that between [WCo(CC 6 H 4 Me-4)(CO) 8 ] and [W(CMe)(CO) 2 (η-C 5 H 5 )] gives [WCo(μ-MeC 2 C 6 H 4 Me-4)(CO) 5 (η-C 5 H 5 )]. The molecular structure of [WCo{μC(C 6 H 4 Me-4)C(O)C(C 6 H 4 Me-4)}(CO) 5 (η-C 5 H 5 )] has been established by X-ray diffraction. The WCo bond (2.669(1) A) is spanned by the C(C 6 H 4 Me-4)C(O)C(C 6 H 4 Me-4) ligand, the terminal carbon atoms of which are σ-bonded to the tungsten and the cobalt atoms (Wμ-C 2.174(5) and 2.195(4), Coμ-C 2.037(8) and 2.053(5) A). Bonding between the tungsten or the cobalt atoms and the central carbon of the μ-C 3 fragment, if present, must be weak (W ⋯ C(O) 2.615(5), Co ⋯ C(O) 2.517(5) A). As expected, the tungsten atom is ligated by the η-C 5 H 5 group and two carbonyl ligands. The cobalt atom carries three terminal carbonyl groups. The reaction between [Mo(CC 6 H 4 Me-4)(CO) 2 (η-C 5 H 5 )] and [WCo(CC 6 H 4 Me-4)(CO) 8 ] affords the dmolybdenum complex [Mo 2 (μ-C(C 6 H 4 Me-4)C(O)C(C 6 H 4 Me-4)}(CO) 4 (η-C 5 H 5 ) 2 ], but the latter is more readily obtained by photolysis of the mononuclear molybdenum 4-tolylmethylidyne compound. Treatment of [WCo(CO) 7 (η-C 5 H 5 )] with diphenylcyclopropenone or MeCCPh gives, respectively, the bridged alkyne complexes [WCo(μ-RC 2 Ph)(CO) 5 (η-C 5 H 5 )] (R = Ph or Me). The 1 H and 13 C-{ 1 H} NMR data for the new compounds are reported and discussed.

Reactions of dimethyldivinylsilane, dimethyldivinyltin and allyltrimethyltin with diethylene (tertiary) phosphine)platinum complexes

Abstract The compounds [Pt(C2H4)2(PR3)] [PR3 = P-tBu2Me, P(C6H11)3, PPh3] react dimethyldivinylsilane or dimethyldivinyltin to give chelate complexes [Pt{(CH2CH)2MMe2} (PR3)] (M = Si or Sn). allyltrimethyltin reacts with various diethylene (tertiary phosphine)platinum compounds with cleavage of the allyl group to afford complexes [Pt(SnMe3)(η3-C3H5)(PR2)]. The NMR spectra (13C, 1H and 31P) of the new compounds have been recorded, and the data are discussed in terms of the structures proposed.

Docosahedral carbaboranetungsten-alkylidyne complexes: synthesis of compounds with heteronuclear metal-metal bonds

Abstract The salts [NEt4][W(CR)(Co)2(η6-C2B10H10Me2)] (R  C6H4Me-4 (Ia) or C6H3Me2-2,6 (Ib)) have been prepared and used to synthesise complexes with bonds between tungsten and gold, rhodium, and iron. The struture of Ib has been established by X-ray diffraction, demonstrating the docosahedral nature of the C2B10W framework.