Vishnu D. Gupta

Neutral five-co-ordinate gallium(III) and indium(III) complexes derived from sulfur ligands

Five-co-ordinated gallium(III) and indium(III) complexes, GaCl[PhC(S)CHC(O)Ph]2, GaCl(S2CNR2)2(R = Me, Pri or NR2= pyrrolyl) and InCl(S2CNPri2)2, have been synthesized and characterized. X-Ray crystallographic studies revealed a trigonal-bipyramidal structure for GaCl[PhC(S)CHC(O)Ph]2 and square-pyramidal structures for GaCl(S2CNMe2)2 and InCl(S2CNPri2)2. Also, Ga(S2CNC4H4)3 has been synthesized. Its molecular structure shows a GaS6 core approaching a trigonal-prismatic geometry.

Preparation and characterization of diorgano- and dihalogeno-bis(monothio-β-diketonato)tin(IV) complexes. Crystal and molecular structures of SnY2(btbm)2 and SnY2(tacac)2(Y = Me or Cl)

Diorgano- and dihalogeno-bis(monothio-β-diketonato)tin(IV) complexes have been prepared and their structures partially deduced by i.r. and n.m.r. data. In order to ascertain structural conclusions, X-ray crystal structure analyses were performed on the complexes SnMe2(btbm)2[Hbtbm = benzoyl(thiobenzoyl)methane] and SnMe2(tacac)2(Htacac = monothioacetylacetone), as well as their dichlorotin(IV) analogues, SnCl2(btbm)2 and SnCl2(tacac)2. The tin atoms in SnMe2(btbm)2 and SnMe2(tacac)2 show a strongly distorted octahedral environment with pairs of the same donor atoms (O, S) in the cis position. The two methyl groups deviate strongly from the trans position, C–Sn–C bond angles being 134.2 and 139.4° respectively. Comparatively long Sn–O bond distances reveal the anisobidentate nature of the ligand. In contrast, the dichloro complexes SnCl2(btbm)2 and SnCl2(tacac)2 exhibit octahedral geometries, the Cl–Sn–Cl bond angles being only 95.3 and 98.5° respectively, with the chlorine atoms in cis positions and the sulphur atoms in trans positions. The oxygen atoms show normal Sn–O bond lengths.

Synthesis and Characterization of the Heterometallic Aggregate Pb2Al5(μ3-O)(μ4-O)(μ-OiPr)9(OiPr)3(μ-OAc)3

A novel heterometallic aggregate Pb2Al5(μ3-O)(μ4-O)(μ-OiPr)9(OiPr)3(μ-OAc)3 obtained from the interaction of Pb(OAc)2 and Al(O–iPr)3 is the first structurally characterized example based on lead and aluminum. This compound has been isolated in high yield and examined by 1H-, 13C-, and 27Al NMR, and in the solid state by X-ray crystallography.

Synthesis, characterization, and crystal structures of tin(IV) 1-pyrrolethiocarboxylates

Tin 1-pyrrolecarbothioates (1-pyrrolethiocarboxylates) SnR4–nLn(L = OSC[graphic omitted]H, n= 1–4) have been synthesized and characterized by i.r., n.m.r. (1H, 13C, and 119Sn), and 119Sn Mossbauer spectral studies. X-Ray crystal and molecular structure analyses were performed on the compounds SnPh3L, SnMe2L2, SnPhL3, and SnL4. The triphenyltin complex is tetrahedral with a sulphur-bonded ligand. The bis complex can be considered to be essentially tetrahedral or as highly distorted octahedral if very weak Sn–O interactions (average bond length 2.65 A) are taken into account. The phenyltin tris complex contains a seven-co-ordinated tin atom in a distorted pentagonal-bipyramidal environment with all the three ligands bound to the tin in an anisobidentate fashion (average Sn–O 2.506 A). The complex SnL4 shows a distorted-octahedral co-ordination geometry with two thiocarbamates functioning as bidentate chelates, the other two as monodentate ligands through the sulphur atom. In solution, these structures are essentially retained, as indicated by the n.m.r. spectral features.

A structural study on gallium and indium β-diketonates

In an attempt to prepare pentacoordinate chlorobis(β-diketonato) gallium(III) and indium(III) complexes only the corresponding tris-products, Ga(PhCOCHCOPh)3 (1), Ga(tBuCOCHCOtBu)3 (1a), and In(PhCOCHCOPh)3 (2), could be isolated. The crystal and molecular structures of 1 and 2 were determined. Both the complexes were found to have triclinc crystal system, with P1 space group. Cell parameters: 1 – a = 9.913(3) Å, b = 10.534(6) Å, c = 18.05(2) Å, α = 93.86(5)°, β = 94.40(4)°, γ = 106.58(4)°, V = 1805(2) Å3, z = 2; 2 – a = 10.507(3) Å, b = 11.448(3) Å, c = 16.322(4) Å, α = 107.38(2)°, β = 97.38(2)°, γ = 102.23(2)°, V = 1792(1) Å3, z = 2.

A Structural Study on Indium Tris-thiocarbamates

Indium tris(thiocarbamates) In(S2CNiPr2)3 (1), In(SOCNiPr2)3 (2) and In(S2CNC4H4)3 (3) have been synthesized and characterized. Variable temperature 1H NMR spectra of 1 and 2 are reported. The X-ray molecular structures of 1 and 3 are found to be quite similar; the symmetry of the In(S2C)3 unit in 3 is close to point group D3 with small asymmetry in the In-S bonds.

Synthesis and molecular structure of tris(benzoyl-thiobenzoyl-methanato-O,S) bismuth(III)

Abstract The title bismuth(III) complexes, Bi[C6H5C(S)CHC(O)C6H4X]3 (X = H, OMe, Cl in para position) have been synthesized and characterized. The crystal and molecular structure of the complex Bi[C6H5C(S)CHC(O)C6H5]3 has been determined. It crystallizes in the triclinic space group P 1 . The molecule associates to a loosely held dimer through a weak BiS interaction forming a highly asymmetrical four-membered Bi2S2 bridge structure.

ARSENIC(III), ANTIMONY(III) AND BISMUTH(III) THIOBENZOATES : CRYSTAL AND MOLECULAR STRUCTURES OF M(SOCR)3 AND PHSB(SOCPH)2

Abstract Tris-thiobenzoates, Arsenic, Antimony, Bismuth Tris-thiobenzoates of arsenic, antimony and bismuth, M(SOCR)3 have been obtained from their oxides and characterized. In the X-ray crystal structure determinations of these, the group 15 atom and the three covalently bonded sulfur atoms are found to constitute a trigonal pyramid, the central atoms lie at a C3 axis. In the bismuth complex the thiobenzoate ligand tends to chelate. However, three comparatively short intermolecular M···S interactions are significant features for these molecules resulting in stacking of trigonal prisms providing an essentially six coordinate environment around arsenic and antimony and a nine-coordinate one for bismuth. The structure of PhSb(SOCPh)2 can be considered

Indium derivatives of monothio-β-diketones and the X-ray structure of tris[benzoyl(thiobenzoyl)methanato-o,s]indium(III)

Six-co-ordinated mono-, bis-, and tris-(monothio-β-diketonates) of iridium(III) have been synthesized and character ized. The X-ray crystal structure of the title compound reveals a distorted octahedral geometry with facia I arrangement of the sulphur and oxygen ligand atoms.

Organosilicon and Organotin Derivatives of N-Aryl Amidoximes

Abstract Some interesting compounds of N-phenyl benzamidoxime and N-m-tolyl benzamidoxime derived from diorganosilicon(IV), triorganotin(IV) and diorganotin(IV) are reported. The molecular weight, infra-red and proton magnetic resonance spectral data suggest stereochemical variations in the compounds.