Bertil Noren

Metal-metal interactions in chain compounds of gold(I): syntheses and crystal structures of chlorotetrahydrothiophenegold(I), bromotetrahydrothiophenegold(I) and iodotetrahydroselenophenegold(I)

Abstract The crystal structures of the title compounds have been determined from X-ray intensity data collected at 200 K with a CAD 4 diffractometer. Crystal data at 200 K (Mo Kα, \ gl = 0.7107 A) are: [Au(C4H8S)Cl], orthorhombic, Pmc2v, Z = 4, a = 6.540(1), b = 8.192(1), c = 12.794(3) A and V= 685.5(2) A3; [Au(C4H8S)Br], orthorhombic, Pmc2v, Z = 4, a =6.564(1), b = 8.328(2), c = 13.229(4) A and V= 723.1(2) A3; [Au(C4H8Se)I], orthorhombic, Pc21n, Z = 8, a = 8.286(2), b = 11.552(3), c = 16.204(6) A and V= 1551.0(5) A3. Full matrix least-squares refinements using reflections obeying I > 2σ(I) converged to R = 0.053 (652 reflections), R = 0.067 (656 reflections) and R = 0.049 (1453 reflections) for the chloro, bromo and iodo compounds, respectively. [Au(C4H8S)Cl] and [Au(C4H8S)Br] are isostructural and comprise linear, neutral complexes, [Au(C4H8S)X], which are stacked in a staggered conformation forming infinite arrays of gold atoms running along a with gold-gold distances of 3.324(1) and 3.353(1) A and Au-Au-Au angles of 159.30(6)° and 156.29(8)° for the chloro and bromo complexes, respectively. The Au-S distances are in the range 2.26-2.28 A for both compounds, indicating that the difference in trans-influence of Cl and Br on the Au-S distance is negligible. [Au(C4H8Se)I] is composed of linear complexes, [Au(C4H8Se)2]+ and [AuI2]−, which alternate in infinite zigzag chains running along b, with Au-Au distances of 2.987(2) and 3.001(2) A and with Au-Au-Au angles of 160.89(4)° and 156.35(4)°. The Au-I and Au-Se distances are in the ranges 2.569(2)–2.571(2) and 2.430(3)–2.436(3) A, respectively. Since there are no ligand bridges between the gold atoms in any of these compounds, the fairly short gold-gold distances indicate metal-metal bonding. A survey of short Au-Au interactions, not supported by ligand bridges, shows a wide range of distances, 2.97 to 3.78 A, with a frequency maximum at 3.2–3.4 A.

Synthesis and crystal structure of potassium tetranitrato palladate(II)

Abstract K 2 [Pd(NO 3 ) 4 ] has been prepared and its crystal structure determined by use of a CAD-4 diffractometer with monochromatic Mo Kα radiation. The space group is P 2 1 / c with Z = 4; a= 7.940(2); b = 15.469(4); c = 9.453(2) A; β = 91.10(3)°. The refinement converged to R = 0.023. The structure contains discrete complexes of [Pd(NO 3 ) 4 ] 2− with pseudosymmetry C 4. Pd coordinates four oxygens from different unidentate nitrato groups. The average Pd-O distance is 2.000(7) A. The coordination around Pd is distorted square-planar, with Pd situated 0.139 A above the plane through the four coordinated oxygens. Similar to [Pt(NO 3 ) 4 ] 2− , but in contrast with [Au(NO 3 ) 4 ] − , all four nitrato ligands are situated on the same side of the coordination plane forming a basket-like structure. This is probably due to interactions between the non-coordinated oxygens of the nitrato ligands and suitably located potassium ions. Comparison with the structure of cis -[Pd- (NO 3 ) 2 (DMSO) 2 ] indicates strong ground-state trans - influence of dimethyl sulfoxide in palladium complexes.

PHENYLATION OF PLATINUM(II) THIOETHER COMPLEXES BY TETRAPHENYLBORATE(III) IN SOLID STATE AND NITROMETHANE SOLUTION

Abstract Platinum(II) complexes of the type [Pt(thioether)3Cl]+ (thioether = dimethyl sulfide, thioxane) are capable of abstracting a phenyl group from the BPh− 4 counterion with formation of trans-[Pt(thioether)2ClPh] compounds. Thermal reactions proceed both in the solid phase and in nitromethane solution at elevated temperature and have preparative importance. Phenylation of the Pt(II) centre also occurs in reaction between [Pt(Me2S)2Cl2] and AgBPh4 in CH2Cl2 suspension. Brief X-ray crystallographic structural data for trans-[Pt(Me2S)2ClPh] and [Pt(thioether)3Cl]X (thioether = Me2S, tx, X = SO3CF3; thioether = Me2S, X = PF6) are reported.

trans influence on bond distances. Structures of trans-diiodobis(tetrahydrothiophene)palladium(II) and trans-diiodobis(tetrahydrothiophene)platinum(II)

Crystals of trans-diiodobis(tetrahydrothiophene)-palladium(II) and trans-diiodobis(tetrahydrothiophene)platinum(II) were prepared by dissolving the appropriate metal iodide in tetrahydrothiophene at 353 K and cooling to room temperature. Crystal data at room temperature (Mo K-alpha, lambda = 0.7107-angstrom) are: [PdI2(C4H8S)2], M(r) = 536.54, triclinic, P1BAR, a = 8.4920 (8), b = 8.8248 (1), c = 9.4580 (11) angstrom, alpha = 97.595 (9), beta = 91.963 (9), gamma = 99.482 (9)-degrees, V = 691.8 (1) angstrom-3, Z = 2, D(x) = 2.576 Mg m-3, mu = 5.997 mm-1, F(000) = 496, R = 0.028 for 2090 unique reflections with I > 3-sigma-(I); [PtI2(C4H8S)2], M(r) = 625.24, triclinic, P1BAR, a = 7.889 (2), b = 8.676 (1), c = 10.616 (2) angstrom, alpha = 103.75 (1), beta = 90.36 (1), gamma = 94.70 (2)-degrees, V = 703.2 (2) angstrom-3, Z = 2, D(x) = 2.953 Mg m-3, mu = 14.67 mm-1, F(000) = 560, R = 0.024 for 3988 reflections with I > 3-sigma-(I). Both compounds consist of van-der-Waals-packed mononuclear trans-[MI2(C4H8S)2] complexes. There are two centrosymmetric metal complexes in the asymmetric unit of the Pt compound but only one pseudoplanar complex in the Pd compound. The acceptor-donor distances are Pd-I 2.603 (1), 2.625 (1); Pd-S 2.316 (2), 2.329 (2); Pt-I 2.606 (1), 2.616 (1); and Pt-S 2.309 (1), 2.310 (1) angstrom. A literature survey of compounds in which ligand-I or -S (in thioethers) atoms are trans to themselves shows average M-I and M-S distances of Pd-I 2.605 (20), Pd-S 2.324 (15), Pt-I 2.609 (9) and Pt-S 2.313 (13) angstrom. The spread of the M-I and M-S distances is significantly increased if complexes are included where I or S are not trans to themselves, indicating that for some donor atoms the trans influence dominates over other factors such as the cis influence and packing forces. (Less)

New methods for synthesis of platinum(II) dimethyl sulfide complexes

Abstract Different methods for the synthesis of anionic dimethyl sulfide platinum complexes of the type Q[PtCl 3 (Me 2 S)] (Q = triphenylbenzylphosphonium, Ph 3 PBzl, or tetrabutylammonium, Bu 4 N) and [Pt(μ-Cl)Cl(Me 2 S)] 2 are reported. The compounds Q[PtCl 3 (Me 2 S)] were prepared by interaction of [PtCl 4 ] 2− with an excess of Me 2 S in non-aqueous media, reduction of [PtCl 5 (Me 2 S)] − with hydrazine sulfate, bridge-splitting reactions of (Ph 3 PBzl) 2 [Pt 2 (μ-Cl) 2 Cl 4 ] and [Pt(μ-Cl)Cl(Me 2 S)] 2 with two equivalents of Me 2 S and (Ph 3 PBzl)Cl, respectively, and substitution of dimethyl sulfide in trans -[PtCl 2 (Me 2 S) 2 ]. The [Pt(μ-Cl)Cl(Me 2 S)] 2 dimer was prepared via reaction of cis -[PtCl 2 (Me 2 S) 2 ] with two equivalents of silver nitrate followed by separation of AgCl(s) and addition of one equivalent of K 2 [PtCl 4 ]. The structure of (Ph 3 PBzl)[PtCl 3 (Me 2 S)] was determined by X-ray single crystal analysis. The compound crystallizes in the space group P 2 1 / n with a = 9.746(3), b = 19.511(4), c = 14.966(4) A, β = 100.43(2)°, V = 2799.0(9) A 3 and Z = 4.