The crystal and molecular structure of a platinum-silatrane complex

1977 ◽  
Vol 30 (5) ◽  
pp. 1007 ◽  
Author(s):  
GR Scollary

A structural analysis of the platinum-silatrane complex, PtCl [Si(OCH2CH2)3N] [PMe2Ph]2, has been carried out by X-ray diffraction. Crystals are monoclinic, space group P21/c, a 6.630(4), b 17.465(6), c 22.297(6) Ǻ, β 97.4(2)�, Z 4. The structure has been refined by a full- matrix least-squares procedure to R 0.048 for 2165 reflections. Basic geometries are square (platinum), tetrahedral (silicon) and trigonal (nitrogen). Within the silatrane ligand, the Si-N non-bonding distance is 2.89(1) Ǻ.

1986 ◽  
Vol 51 (11) ◽  
pp. 2521-2527 ◽  
Author(s):  
Jan Lokaj ◽  
Eleonóra Kellö ◽  
Viktor Kettmann ◽  
Viktor Vrábel ◽  
Vladimír Rattay

The crystal and molecular structure of SnBu2(pmdtc)2 has been solved by X-ray diffraction methods and refined by a block-diagonal least-squares procedure to R = 0.083 for 895 observed reflections. Monoclinic, space group C2, a = 19.893(6), b = 7.773(8), c = 12.947(8) . 10-10 m, β = 129.07(5)°, Z = 2, C20H38N2S4Sn. Measured and calculated densities are Dm = 1.38(2), Dc = 1.36 Mg m-3. Sn atom, placed on the twofold axes, is coordinated with four S atoms in the distances Sn-S 2.966(6) and 2.476(3) . 10-10 m. Coordination polyhedron is a strongly distorted octahedron. Ligand S2CN is planar.


1988 ◽  
Vol 41 (5) ◽  
pp. 641 ◽  
Author(s):  
GB Robertson ◽  
PA Tucker

The structure of mer-(Pme2Ph)3Cl-cis-H2IrIII (1) has been determined by single-crystal X-ray and neutron diffraction analyses. Crystals are monoclinic, space group P21, with a 11.476(4), b 14.069(5), c 8.286(3)Ǻ, β 92.45(1)° and Z 2. Full-matrix least-squares analyses converged 0.022 for 7773 X-ray data and R(F2) = 0.062 for 1538 neutron data. Ir -H [1.557(11)Ǻ trans to Cl, 1.603(10) Ǻ trans to P] and Ir -P distances [2.292(1)Ǻ trans to P, 2.328(1)Ǻ trans to H] both exhibit trans lengthening effects. Consistent with the increased hydride content the Ir -P distances in (1) are c. 0.04 Ǻ shorter than for the corresponding bonds in its dichloro monohydrido analogues and c. 0.08 Ǻ shorter than those in the trichloride . In contrast Ir-Cl [2.505(1)Ǻ] is not significantly different to the corresponding distance (2.504 Ǻ av.) in mer -(PMe2Ph)3-cis-Cl2HIrIII.


1983 ◽  
Vol 61 (6) ◽  
pp. 1185-1188 ◽  
Author(s):  
Hans Koenig ◽  
Richard T. Oakley ◽  
A. Wallace Cordes ◽  
Mark C. Noble

The reaction of tetrasulphur dinitride with norbornadiene produces the 1:1 adduct S4N2•C7H8; X-ray crystallographic analysis of this compound reveals that olefin addition cleaves one of the sulphur–sulphur bonds of S4N2, yielding a novel eight-membered C2S4N2 ring. Crystals of S4N2•C7H8 are monoclinic, space group P21/c, a = 6.127(1), b = 17.369(1), c = 9.580(1) Å, β = 106.74(1)°, V = 1003.8(5) Å3Z = 4. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to R = 0.039. The S—S—N—S—N—S fragment of the C2S4N2 ring is planar to within 0.15 Å. The S—C—C—S unit is folded out of this plane to produce a dihedral angle of 74.5°.


1975 ◽  
Vol 53 (22) ◽  
pp. 3383-3387 ◽  
Author(s):  
Joseph Hubert ◽  
André L. Beauchamp ◽  
Roland Rivest

The crystal and molecular structure of dithiocyanato(triphenylarsine)mercury(II) has been determined from X-ray diffraction data. The crystals are monoclinic, space group P21/c, with a = 10.290(7), b = 21.199(23), c = 10.719(7) Å, β = 112.00(2)°, and Z = 4. The structure has been solved by the heavy-atom method and refined by block-diagonal least-squares calculations. The agreement factor R obtained for 2607 'observed' reflections is 0.030. The crystal consists of single molecules. The 'characteristic' coordination number of mercury is three, with two sulfur and one arsenic atoms at the apexes of a triangle. The nitrogen atoms of the thiocyanate groups are at 2.67 and 2.74 Å from the adjoining mercury atoms and therefore link the different molecules together.


1979 ◽  
Vol 57 (2) ◽  
pp. 174-179 ◽  
Author(s):  
A. Wallace Cordes ◽  
Paul F. Schubert ◽  
Richard T. Oakley

The crystal structure of 1,4-diphenyl-2,2′,3,3′,5,5′,6,6′-octamethylcyclo-1,4-diphospha-2,3,5,6-tetrasilahexane, (PhPSi2Me4)2, has been determined by single crystal X-ray diffraction. The crystals are monoclinic, space group P21/c, with a = 9.866(1), b = 11.921(1), and c = 11.324(2) Å, β = 104.31(1)°, Z = 2, and ρcalcd = 1.15 g/cm3. The structure was solved by direct methods and was refined by full-matrix least-squares procedures to a final R of 0.060 and Rw of 0.078, for 1173 reflections with intensities greater than 3σ. The (PhPSi2Me4)2 molecule lies on a crystallographic centre of symmetry, and the six-membered P2Si4 ring has a chair conformation with equatorial phenyl groups. The endocyclic angles at P (104.4(1)°) and Si (104.9(2)°) are intermediate between those found in cyclic hexaphosphine and hexasilane molecules, and the Si—Si and P—Si distances of 2.345(3) and 2.252(4) Å, respectively, correspond to single bond lengths, with no appreciable evidence for secondary pπ → dπ bonding between phosphorus and silicon. The Si—C (1.867(8) Å) and P—C (1.828(7) Å) bond lengths are also normal. The variations in the Si—P—C (101.6(2)°, 108.6(2)°), P—Si—C (range 106.2(3)–120.0(3)°), and Si—Si—C (range 105.8(3)–113.7(3)°) angles indicate that the positions of the exocyclic methyl and phenyl groups are influenced by both intra- and intermolecular steric forces.


1997 ◽  
Vol 75 (5) ◽  
pp. 475-482 ◽  
Author(s):  
Wei Xu ◽  
Alan J. Lough ◽  
Robert H. Morris

New amineruthenium and amineiridium hydride derivatives have been synthesized and characterized with the objective of observing intramolecular [Formula: see text] or [Formula: see text] interactions. These include RuHCl(CO)(L)(PPri3)2 (1a, L = NH2NH2; 1b, L = NH3) and IrCl2(L)(H)(PCy3)2 (2a, L = SC(NH2)2; 2b, L = NH3; 2c, L = NH2NH2; 2d, L = NH2(CH2)3NH2; 2e, L = NH2OH). Instead, weak [Formula: see text] van der Waals contacts have been detected in the solid state by X-ray analysis and in solution by NMR T1 measurements and nOe techniques. Both X-ray crystal structure analysis and minimum T1 measurements indicate that the [Formula: see text] distances in the [Formula: see text] interactions are ca•2.0–2.2 Å. The weak interactions might influence the course of deuteration of these complexes under D2 gas. The crystal and molecular structure of IrCl2(NH3)(H)(PCy3)22a has been determined by X-ray diffraction at 173 K: monoclinic, space group P21/n, a = 14.859(2) Å, b = 18.579(3) Å, c = 18.548(3) Å, β = 97.29(1)°, V = 5079.1(13) Å3, Z = 4, full-matrix least-squares refinement on F2 for 10 953 independent reflections; R[F2 > 4σ(F2)] = 0.0283, wR(F2) = 0.0704. Keywords: ruthenium, iridium, hydride, dihydrogen, complexes, hydrogen bond, NMR, X-ray.


1994 ◽  
Vol 72 (4) ◽  
pp. 1154-1161 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Steven J. Rettig ◽  
James Trotter

Three 2-(hydroxyamino)alkanols have been reacted with sterically hindered arylboronic acids, ArB(OH)2. When Ar = o-tolyl, 1:2 condensates having bicyclic structures are formed but when Ar = mesityl (2,4,6-(CH3)3C6H2), 1:1 condensates having six-membered cycloboronate structures result. These 1:1 condensates represent the first examples of N-unsubstituted 1,3-dioxa-4-aza-2-boracyclohexane derivatives. An X-ray analysis of one example provides unambiguous proof of the structure. Crystals of 2-mesityl-6,6-pentamethylene-1,3-dioxa-4-aza-2-boracyclohexane, 3c, are monoclinic, a = 11.076(9), b = 23.94(2), c = 13.414(9) Å, β = 109.40(5)°, Z = 8, space group P21/n. The structure was solved by direct methods and refined by full-matrix least-squares procedures to R = 0.051 and Rw = 0.058 for 2037 reflections with I ≥ 3σ(F2).


1998 ◽  
Vol 51 (3) ◽  
pp. 219 ◽  
Author(s):  
Ian R. Whittall ◽  
Mark G. Humphrey ◽  
David C. R. Hockless

The structures of Ni(C≡CR)(PPh3)(η-C5H5) (R = Ph (1), C6H4-4-NO2 (2), 4-C6H4C6H4-4′-NO2 (3), (E)-4-C6H4CH=CHC6H4-4′-NO2 (4), 4-C6H4C≡CC6H4-4′-NO2 (5), 4-C6H4N=CHC6H4-4′-NO2 (6)) have been determined by single-crystal X-ray diffraction studies, refining by full-matrix least-squares analysis. For (1), crystals are triclinic, space group P-1, with a 10·094(2), b13·429(3), c 18·835(5) Å,α 103·24(2), β 91·50(2), γ 90·10(2)°, Z 4, 5844 unique reflections (595 parameters), converging at R 0·033 and Rw 0·024. For (2), crystals are orthorhombic, space group Pna21, with a 16·799(2), b 8·681(2), c 17·485(2) Å, Z 4, 1774 unique reflections (325 parameters), converging at R 0·031 and Rw 0·029. For (3), crystals are monoclinic, space group P 21/c, with a 11·140(3), b 18·282(4), c 15·296(2) Å, β 105·18(2)°, Z 4, 3132 unique reflections (397 parameters), converging at R 0·039 and Rw 0·024. For (4), crystals are monoclinic, space group P 21/n, with a 12·929(7), b 16·953(8), c 15·601(7) Å, β 112·55(3), Z 4, 3023 unique reflections (397 parameters), converging at R 0·039 and Rw 0·025. For (5), crystals are monoclinic, space group P 21/n, with a 12·710(5), b 16·882(3), c 15·693(4) Å, β 111·37(3)°, Z 4, 3216 unique reflections (397 parameters), converging at R 0·035 and Rw 0·030. For (6), crystals are monoclinic, space group P 21/n, with a 12·594(1), b 16·936(2), c 15·611(1) Å, β 112·476(5)°, Z 4, 3564 unique reflections (397 parameters), converging at R 0·038 and Rw 0·041. For structurally characterized 18-electron (cyclopentadienyl)nickel(II) acetylide complexes, statistically insignificant decreases in the average Ni-C(1) distance and trans influence and an increase in the average C(1)-C(2) parameter are observed on introduction of an acceptor substituent at the alkynyl ligand.


1995 ◽  
Vol 48 (7) ◽  
pp. 1277 ◽  
Author(s):  
EJ Ditzel ◽  
GB Robertson

The structure of mer-trans-(PPri3)2(PH3)H-trans-Cl2IrIII (1) (Pri = isopropyl), the second third-row transition-metal-PH3 complex to be so characterized, has been determined by single-crystal X-ray diffraction analysis. Crystals are monoclinic, space group C 2/c with a 21.701(2), b 8.735(1), c 15.594(1) Ǻ, β 119.57(1)° and Z 4. Structure refinement by full-matrix least-squares analysis (2811 reflections, 113 parameters) converged with R = 0.016 and Rw = 0.022. Molecules exhibit crystallographically imposed C2 symmetry. The C2 axis passes through the iridium, hydride and PH3 phosphorus atoms, and requires the PH3 hydrogen atoms to be disordered. Important molecular dimensions are Ir-PPri3 2.371(1) Ǻ, Ir-PH3 2.362(1) Ǻ, Ir-Cl 2.374(1) Ǻ and P- Ir -P(trans) 163.21(3)°.


1996 ◽  
Vol 49 (11) ◽  
pp. 1253 ◽  
Author(s):  
EJ Ditzel ◽  
KD Griffiths ◽  
GB Robertson

The structure of mer-cis-(PEt2Ph)2(PPri3)H-trans-Cl2IrIII (4) has been determined by single-crystal X-ray diffraction analysis. Crystals are monoclinic, space group P21/c, with a 11.607(1), b 21.553(1), c 14.066(1) Ǻ, β 109.04(1)? and Z 4. Structure refinement by full-matrix least-squares analysis (3244 unique reflections, 316 parameters) converged with R 0.034 and Rw 0.041. The PEt2Ph ligands are similarly disposed to their PMe2Ph counterparts in mer-cis-(PEt2Ph)2(PPri3)H-trans-Cl2IrIII (2) but the PPri3 ligands are differently oriented and differently configured. Metal-ligand distances [ Ir -P(1,2,3) 2.333(2), 2.404(2), 2.368(2) Ǻ; Ir-Cl (1,2) 2.388(2), 2.400(2) Ǻ] are all within c. 0.02 Ǻ of those in (2). The P-Ir -P(trans) angle is 155.3(1)°.


Sign in / Sign up

Export Citation Format

Share Document