The title compound is a novel mixed ligand and mixed valence complex of tellurium, the crystal structure of which is reported here. The compound crystallizes in the orthorhombic space group, Pca21 with four molecules per unit cell, the dimensions of which are a=15.209(1), b=20.159(2), c=12.453(1) Å. The structure was solved by the heavy-atom method and refined by fullmatrix least-squares method to a final R=0.046 and Rw=0.046 for 3011 unique reflections. The structure could be considered as 1:1 adduct of TeIVL2I2 and TeIILI (L=diisopropyldithiocarbamate). The two tellurium atoms, TeII[Te(1)] and TeIV[Te(2)] display entirely different coordinations and are bridged through iodine I(1) in a symmetrical manner. There is a short Te(1)⋯Te(2) contact distance of 3.542(1) Å. © 1989 Plenum Publishing Corporation.

Maha Seshasayee

S. P. Chidambaram

Gopalaswamiengar Aravamudan

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

A novel mixed valence iodide bridged Te(II)-Te(IV) complex featuring diisopropyldithiocarbamate(L) and iodide: ILTeII(I)TeIVL2I

Journal of Crystallographic and Spectroscopic Research

The title compound, SeLBr [L- = diethyldithiocarbamate, (C2H5)2NCS- 2] is the first example of Se(II) complex featuring a dithiocarbamate and a halide. It was obtained by the reaction of Se(IV)bromide with tetraethylthiuram disulfide in a methanol solution containing hydrobromic acid. The structure determination of the compound shows it to be polymeric with bromine being the bridging ligand. The crystals of SeLBr are monoclinic with a = 10.391(3), b = 8.434(4), c = 12.030(2) Å, β = 108.10(2)°, V = 1002.15 Å3, Z = 4 and space group, P21/n; R = 0.073, Rw = 0.074.

Phosphorus, Sulfur and Silicon and Related Elements

Synthesis and structure of the first mixed halide-dithiocarbamate complex of Se(II), bromodiethyldithiocarbamatoselenium(II), [Se{(C2H5)2NCS2}Br]

The title mixed ligand complex was synthesized by the controlled oxidative displacement reaction of TeL4″ by iodine (L″ is diisopropyldithiocarbamate ion). Its crystals are monoclinic, space group P21 with Z=2 in a unit cell of dimensions a=8.344(4), b=14.113(8), c=10.647(5) Å, β=99.884(2)°, and V=1235.15 Å3, final R=0.043 and Rw=0.047 for 3553 unique reflections. The central tellurium atom shows a S4I2 six coordination with the two dithiocarbamate groups almost isobidentate, the average Te-S and the Te-I distances being 2.571(3) and 3.011(1) Å, respectively. The structure is monomeric in the solid state. No intermolecular short contacts are observed. © 1991 Plenum Publishing Corporation.

Synthesis and structure of bisiodobis(diisopropyldithiocarbamato)tellurium(IV)

Mixed halo dithiocarbamate complexes of TeII were synthesized for the first time. Complexes of the general formula Te2L3X (X = SCN-, Br- and I-) were obtained from the parent compound TeL2 [L = bis(2-hydroxyethyl)dithiocarbamate] and potassium thiocyanate or halides in acetic acid medium. Their chemical and physical properties were studied and the crystal structure of the thiocyanate compound determined. The crystals of the thiocyanate complex are monoclinic, with space group P 21 /n, a 14•056(3), b 9•599(2), c 22•519(6) Å, β 105•71(2)°, V 2924•8 Å3, Z 4, F(000) 1672, the final R and Rw values being 0•042 and 0•041 respectively for 1209 unique reflections. Many novel aspects were observed in the structure. The two tellurium atoms display entirely different coordinations. One of them, namely, Te(1), has two unequal bidentate dithiocarbamate groups chelated to it in planar-trapezoidal coordination similar to the geometry found in the parent TeL2 complex. It is also linked to Te(2) by a short contact [3•221(3) Å] to complete the fifth coordination. The second tellurium atom Te(2) exhibits trapezoidal four-coordination with an equal bidentate dithiocarbamate group, an S-bonded thiocyanate group, and interestingly with Te(1). The Te(1)-Te(2) axis is inclined with respect to the Te(1)-S(1)-S(2)-S(3)-S(4) plane (trapezoid) by 67•6°. © 1985 ASEG.

Australian Journal of Chemistry

Synthesis and Properties of Tris[bis(2-hydroxyethyl)dithiocarbamato]haloditellurium(II) (‘halo’ = SCN-, Br-, I-) and the Crystal Structure of the Thiocyanato-S Complex, [Te2 ((HOCH2CH2)2NCS2)3SCN]

The synthesis, properties, and structural characterization of the title compound, C16H30N4O4S7Te(IV)·H2O, are reported. The crystals are monoclinic, space group P21/n, with Z=4 in a unit cell of dimensions a=13.291(5), b=21.306(6), c=10.450(1) Å, 0=104.25(2)° and, Vc=2868 Å3. The structure was solved by the heavy atom method and refined by full-matrix least squares to R=0.025 and Rw=0.027 for 2894 reflections. The dithiocarbamate groups are linked in an unequal bidentate manner with Te-S average distance 2.695(1) Å. The thiocyanate group is bonded through the sulfur atom with much larger Te-S length [2.964(2) Å]. © 1984 Plenum Publishing Corporation.

Journal	Journal of Crystallographic and Spectroscopic Research
Publisher	Kluwer Academic Publishers-Plenum Publishers
ISSN	02778068
Open Access	No