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41.
The structure of a bis(benzyloxy)trishomocubanone with molecular C2 symmetry reveals that substitution of benzyloxy groups has little effect on the trishomocubane cage. 相似文献
42.
Huafeng Shen Jian Cheng Wang Simon G. Bott Michael G. Richmond 《Journal of chemical crystallography》1997,27(11):649-656
Thermolysis of Ru3(CO)12 with 2,3-bis(diphenylphosphino)maleic anhydride (bma) in toluene solution gives the new compounds Ru3(CO)10(bma) (2), Ru2(CO)6(bma) (3), and (4). All compounds have been isolated and characterized in solution by IR and31P NMR spectroscopy. The solid-state structures of2, as the monohydrate, and4 were established by X-ray crystallography. Ru3(CO)10(bma)·H2O crystallizes in the monoclinic space groupC2/c,a=12.741(2) Å,b=19.548(2) Å,c=32.973(4) Å, β=96.847(9)°,V=8154(2) Å3,Z=8,d calc=1.740 g cm?3;R=0.046,R w =0.051 for 2541 observed reflections withl>3σ(l). The bma ligand in2 is bound to the triruthenium frame in a bridging fashion, with equatorially disposed PPh2 groups. The X-ray structure of2 reveals an extreme twisting of the maleic anhydride ring away from the plane defined by the plane of the three ruthenium atoms, along with a significant lengthening of the maleic anhydride C=C π bond. crystallizes in the monoclinic space groupP21/c,a=9.3113(5) Å,b=18.164(1) Å,c=20.097(1) Å, β-102.021(4)°,V=3324.5(3) Å3,Z=4,d calc=1.671 g cm?3;R=0.024,R w =0.030 for 3499 observed reflections withl>3σ(l). The presence of the μ2 moiety and P?C (maleic anhydride) bond cleavage attendant in the formation of4 are confirmed by X-ray analysis. The relationship of the compounds3 and4 to the dimeric compounds Ru2(CO)6(bpcd) and [where bpcd=4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] is discussed. Independent studies dealing with Ru3(CO)10(bma) (bridging isomer) have shown that cluster2 is stable in toluene solution at elevated temperature and does not afford compounds3 and4, suggesting the intermediacy of the putative chelating isomer of Ru3(CO)10(bma) (1) as the source of3 and4. 相似文献
43.
Simon G. Bott Kaiyuan Yang Michael G. Richmond 《Journal of chemical crystallography》2004,34(2):127-133
Treatment of the diphosphine ligand 1,2-bis(diphenylphosphino)cyclobutenedione (bpcbd) with the THF adduct fac-BrRe(CO)3(THF)2 at room temperature furnishes the new dirhenium compound [BrRe(CO)3]2(bpcbd) instead of the expected mononuclear compound fac-BrRe(CO)3(bpcbd). [BrRe(CO)3]2(bpcbd) was characterized in solution by IR spectroscopy, and the solid-state structure was solved by X-ray crystallography. [BrRe(CO)3]2(bpcbd), as the CH2Cl2 solvate, crystallizes in the space group P
, a = 11.173(1), b = 13.362(1), c = 15.250(1) Å, = 108.973(7)°, = 99.477(8)°, = 110.466(7)°, V = 1915.0(3) Å3, Z = 2, and d
calc = 2.143 g-cm–3. The structure of [BrRe(CO)3]2(bpcbd) consists of two rhenium centers that are six-coordinate and possess nearly ideal octahedral geometry. The two Re(CO)3 units are linked together by the bridging diphosphine ligand and two bridging bromide groups. 相似文献
44.
Michael P. Castellani William G. Smith Nimish G. Patel Simon G. Bott Michael G. Richmond 《Journal of chemical crystallography》1999,29(5):609-617
The reaction between the tricobalt cluster Co3(CO)9(3-CCl) (1) and AlCl3, followed by treatment with ethyl diazoacetate, N2CHCO2Et, affords a complex mixture of products in low yields. Column chromatography has allowed the isolation of the four cluster compounds Co3(CO)9(3-CH) (2), Co3(CO)9(3-CCO2Et) (3), Co3(CO)9(3-CCH2CO2Et) (4), and [Co3(CO)9(3-CCHCO2Et)]2 (5). Clusters 4 and 5 are new and have been fully characterized in solution by IR and 1H NMR spectroscopy. The molecular structures of clusters 3–5 have also been determined by single-crystal X-ray diffraction analysis. Co3(CO)9(3-CCO2Et) crystallizes in the triclinic space group P
, a = 8.8393(5), b = 14.727(1), c = 15.272(1) Å, = 93.361(6), = 105.509(5)°, = 100.336(6)°, V = 1872.6(2) Å3, Z = 4, and d
calc = 1.823 g/cm3. Co3(CO)9(3-CCH2CO2Et) crystallizes in the monoclinic space group P21/n, a = 9.3806(7), b = 9.2617(8), c = 22.455(2) Å, = 94.483(7)°, V = 1944.9(3) Å3, Z = 4, and d
calc = 1.803 g/cm3. [Co3(CO)9(3-CCHCO2Et)]2 crystallizes in the monoclinic space group C2/c, a = 21.585(2), b = 8.7977(7), c = 20.784(1) Å, = 104.807(6)°, V = 3815.8(5) Å3, Z = 4, and d
calc = 1.835 g/cm3. Plausible pathways leading to the formation of clusters 2,
4, and 5 are discussed. 相似文献
45.
C. Jeff Harlan Simon G. Bott Andrew R. Barron 《Journal of chemical crystallography》1998,28(8):649-651
Reaction of AlH3[N(CH2CH2)3CH] with hexamethyltrisiloxane, (OSiMe2)3, gives rise to the bis-quinuclidine complex AlH3[N(CH2CH2)3CH]2, which has been characterized by 1H and 13C NMR spectroscopy and X-ray crystallography. The molecular structure of AlH3[N(CH2CH2)3CH]2 consists of a trigonal bipyramidal aluminum with axial coordination of the quinuclidine ligands. Crystal data: orthorhombic, space group Pbcn, a = 10.6895(9), b = 12.266(1), c = 12.3794(9) Å, V = 1623.2(2) Å3, and Z = 4. 相似文献
46.
Cullen T. Vogelson Christopher L. Edwards Andrew N. Kobylivker Star B. Chacko Cristin E. Moran Kathryn Dalton Shawn M. Stewart Brian C. Werner Simon G. Bott Andrew R. Barron 《Journal of chemical crystallography》1998,28(11):815-824
The molecular structures of Al(tfac)3 (1), Co(tfac)3 (2) (H-tfac = 1,1,1-trifluoroacetylacetone) and Cu(H2O)(fod)2 (3) (H-fod = 1,1,1,2,2,3,3-hepta-fluoro-7,7-dimethyloctane-4,6-dione) have been determined. The metal coordination spheres in compounds 1 and 2 are essentially the same as the respective M(acac)3 derivatives. Despite the isomorphous nature of the structures of compounds 1 and 2, the identity of the nearest intermolecular van der Waals contacts are altered by minor changes in the metal coordination sphere. The geometry about copper in compound 3 is close to that of an ideal square bipyramid with the -diketonate ligands occupying the basal plane. The water ligand in each molecule of compound 3 is hydrogen bonded to an oxygen of a -diketonate ligand on an adjacent molecule resulting in the formation of dimers, which form rods along the y-axis due to weak C–F···Cu interactions. Crystal data: (1) orthorhombic, Pca21, a = 14.949(3), b = 19.806(4), c = 13.624(3) Å, V = 4033(1) Å3, and Z = 8, and (2) orthorhombic, Pca21, a = 14.930(3), b = 19.620(4), c = 13.540(3) Å, V = 3966(1) Å3, and Z = 8,; (3) monoclinic, P21/c, a = 12.447(3), b = 10.486(2) c = 21.980(4) Å, = 102.65(3)°, V = 2799(1) Å3, and Z = 4. 相似文献
47.
Simon G. Bott Alan P. Marchand Duddu Raja Gopal 《Journal of chemical crystallography》1993,23(11):849-855
The syntheses and crystal structures of pentacyclo[9.4.1.05,14.07,13.012,15]hexadecane-3,9-dione (2), a novel C16 diketone with potential inclusion ability, and the products of the reaction of2 withn-butyllithium andmeso-erythritol (i.e.,meso-1,2,3,4-butanetetrol) are described. Crystal data:2·H2O, orthorhombic,Pmmn,a=10.7385(8),b=9.0188(6),c=6.8411(4)Å,V=662.55(7)Å3, andR=0.039 (379 reflections);3 (product from reaction withn-butyllithium), triclinic,P¯1,a=8.7192(7),b=10.9351(8),c=12.1842(8)Å,=68.933(5),=75.850(6), =80.309(6)°,V=1047.0(1)Å3, andR=0.081 (1811 reflections);4 (product from reaction with erythritol), triclinic,P¯1,a=7.7224(8),b=10.1976(8),c=10.7021(9)Å,=85.405(7),=85.766(8), =76.056(7)°,V=814.0(1)Å3, andR=0.052 (1471 reflections). 相似文献
48.
Huafeng Shen Jian Cheng Wang Simon G. Bott Michael G. Richmond 《Journal of chemical crystallography》1994,27(11):649-656
Thermolysis of Ru3(CO)12 with 2,3-bis(diphenylphosphino)maleic anhydride (bma) in toluene solution gives the new compounds Ru3(CO)10(bma) (2), Ru2(CO)6(bma) (3), and
(4). All compounds have been isolated and characterized in solution by IR and31P NMR spectroscopy. The solid-state structures of2, as the monohydrate, and4 were established by X-ray crystallography. Ru3(CO)10(bma)·H2O crystallizes in the monoclinic space groupC2/c,a=12.741(2) ?,b=19.548(2) ?,c=32.973(4) ?, β=96.847(9)°,V=8154(2) ?3,Z=8,d
calc=1.740 g cm−3;R=0.046,R
w
=0.051 for 2541 observed reflections withl>3σ(l). The bma ligand in2 is bound to the triruthenium frame in a bridging fashion, with equatorially disposed PPh2 groups. The X-ray structure of2 reveals an extreme twisting of the maleic anhydride ring away from the plane defined by the plane of the three ruthenium
atoms, along with a significant lengthening of the maleic anhydride C=C π bond.
crystallizes in the monoclinic space groupP21/c,a=9.3113(5) ?,b=18.164(1) ?,c=20.097(1) ?, β-102.021(4)°,V=3324.5(3) ?3,Z=4,d
calc=1.671 g cm−3;R=0.024,R
w
=0.030 for 3499 observed reflections withl>3σ(l). The presence of the μ2 moiety and P−C (maleic anhydride) bond cleavage attendant in the formation of4 are confirmed by X-ray analysis. The relationship of the compounds3 and4 to the dimeric compounds Ru2(CO)6(bpcd) and
[where bpcd=4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] is discussed. Independent studies dealing with Ru3(CO)10(bma) (bridging isomer) have shown that cluster2 is stable in toluene solution at elevated temperature and does not afford compounds3 and4, suggesting the intermediacy of the putative chelating isomer of Ru3(CO)10(bma) (1) as the source of3 and4. 相似文献
49.
A series of five gold(I) halide complexes with the two isomeric methoxy-substituted triarylphosphines, tris(2-methoxyphenyl)phosphine [P(oanis)3], [AuP(oanis)3X] [for X = Cl, (1); X = Br, (2) and X = I, (3)] and tris(4-methoxyphenyl)phosphine [P(panis)3], [AuP(panis)3X] [for X = Br (4) and X = I (5)] have been synthesized and characterized by single crystal X-ray diffraction and solution 31P{1H} NMR spectroscopy. The structure determinations confirm the expected presence of linear two-coordination about the gold centres in all five complexes with bond distance and angle data typical of this type of compound [Au–P, 2.239(2)–2.259(3) Å; Au–Cl, 2.294(2) Å; Au–Br, 2.385(2)–2.402(2) Å; Au–I, 2.546(1)–2.554(1) Å; P–Au–X; 175.3(1)–180°]. All analogues except the iodo complex 5 crystallize with one complex molecule in the crystallographic asymmetric unit. The bromo and iodo complexes 2 and 3 constitute a trigonal isomorphous set while the bromo complex 4 is also isomorphous with the previously determined chloro complex [AuP(panis)3Cl]. The 2-methoxy analogues are stabilized by significant methoxy-O?Au interactions. 相似文献
50.
Sibert JW Forshee PB Hundt GR Sargent AL Bott SG Lynch V 《Inorganic chemistry》2007,46(25):10913-10925
Two series of isomeric, redox-responsive azacrown ethers based on ortho- and para-phenylenediamine (Wurster's crowns) have been synthesized and their properties explored through 13C NMR spectroscopy, electrospray ionization mass spectrometry, cyclic voltammetry, and X-ray crystallography. These crowns display strong affinity for alkali metal cations while maintaining comparable selectivity profiles to the parent crown ethers from which they are derived. Like Wurster's reagent (N,N,N',N'-tetramethyl-p-phenylenediamine or para-TMPD), the para-Wurster's crowns undergo two reversible one-electron oxidations. The integrity of the alkali metal ion complexes is maintained in the neutral and singly oxidized ligand states but not after removal of two electrons. In contrast, the oxidation of ortho-Wurster's crowns is scan rate dependent, occurring at potentials substantially higher than their para counterparts, with their complexes oxidizing irreversibly. X-ray crystal structures of representative complexes show, in all cases, participation of the redox-active phenylenediamine subunits in complex formation via direct bonding to the guest cation. 相似文献