Ali Z. Al-Rubaie

Synthesis and spectroscopic investigations of 1-organo-1-halo-1-telluracyclopentane

Abstract A new class of cyclic telluronium salts has been prepared. All the salts are stable in solution in CHCl 3 or dimethylsulphoxide (DMSO). Conductivity measurements in DMSO and dimethylformamide (DMF) have shown that considerable ion pairing occurs in solution. Infrared, 1 H, 13 C, 125 Te NMR, and mass spectra are reported and discussed.

Heterocyclic tellurium compounds as ligands; some complexes of rhodium(III) and rhodium(I)

Abstract The synthesis and characterization of new rhodium(III) complexes containing tellurium heterocyclic ligands are described. All complexes have the general formula of RhCl 3 L 3 (where L = C 4 H 8 Te, C 4 H 8 TeI 2 , C 4 H 8 OTe, C 5 H 8 Te, C 6 H 10 Te, C 8 H 5 ClTe, C 10 H 12 Te and C 16 H 10 Cl 2 Te). Reactions of RhCl 3 L 3 complexes with carbon monoxide are shown to replace only one cyclic telluride by carbon monoxide under mild conditions. Reactions of square-planar rhodium(I) complexes with tellurium heterocycle ligands are reported.

New cyclic tellurides. Synthesis, reaction and ligand properties of 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te). X-Ray structure determination of C6H16OSi2TeI2

Abstract A new tellurium-containing heterocyclic compound, 2,2,6,6-tetramethyl-1-oxa-4-tellura-2,6-disilacyclohexane (C6H16OSi2Te) (1), has been prepared by treatment of 1,3-bis(chloromethyl)-1,1,3,3-tetramethyldisiloxane with sodium telluride. Mononuclear and dinuclear palladium complexes of this telluride have been prepared by the reaction of 1 with PdCl2(PhCN)2 and Na2PdCl4, respectively. The following new derivatives of 1 have also been produced: C6H16OSi2TeI2 (2), C6H16OSi2TeBr2, C6H16OSi2TeCl2, C6H16OSi2Te(CH3)I, and C6H16OSi2Te(CH2Ph)Br. IR, 1H and 13C NMR and mass spectral data of these new compounds are reported and discussed. 1H NMR studies revealed that in CDCl3 solution both telluronium salts reductively eliminate alkyl halide. The crystal structure of compound 2 has been determined by X-ray diffraction. The compound crystallizes in the monoclinic space group, P21/c, with four molecules in a unit cell of dimension a 12.960(3), b 8.846(2), c 13.754(4) A, β 92.44(2)°, R = 0.049, and Rw = 0.067 for 3599 unique reflections with |F0| > 3σ(F0). The compound forms a six-membered ring of a slightly displaced boat type. The geometry about the Te atom is pseudo-octahedral, with two carbon atoms (Te-C = 2.156(7) and 2.137(6) A) and two iodine atoms of the neighbouring molecules (weak intermolecular bonds, Te · I = 3.769 and 3.806 A) in the equatorial positions and two iodine atoms (Te-I = 2.909(1) and 2.913(1) A) in the axial positions.

Synthesis and study on telluronium salts based on 1-oxa-4-organo-4-telluracyclohexane cation

Abstract A new series of heterocyclic telluronium salts (C4H8OTeRX: R=CH3CH2, CH2CHCH2, CH3, C4H9, X=I; R=CH2CHCH2, X=Br; R=CH3, X=ClO4; R=CH3, CH3CH2, C6H5, X=BPh4) have been prepared. Conductivity measurements in dimethylsulphoxide (DMSO) and N,N-dimethytl- formamide (DMF) have shown that there is an ion pair interaction between the anion and the tellurium cation. 1H NMR studies showed that there is no reaction between the solute and the solvent. All compounds are stable in solution in DMSO. Infra-red spectra are reported and discussed.

Synthesis and characterization of new organotellurium compounds containing an ortho-amino group

Abstract A range of novel organotellurium compounds with an amino group ortho to the tellurium atom (i.e. ArTeBr3 and Ar2Te, where Ar = 2-NH2-5-RC6H3; R = CH3, Br, NO2) have been prepared by a convenient new route involving reaction of the corresponding 2-aminoarylmercury chloride with tellurium tetrabromide. Reduction of ArTeBr3 gave the compounds Ar2Te2 in good yield; these were treated with chlorine to give ArTeCl3 in quantitive yield.

2-Methyl-1-organo-1-halo-1-telluracyclopentane: synthesis, solution properties, and configurational studies

Abstract Some new heterocyclic tellurium compounds containing the 2-methyl-1-organo-1-telluracyclopentane cation have been prepared. 1 H NMR studies show the presence of cis/trans geometrical isomers. The effect of organyl group and theanion on the cis/trans ratio have been investigated. All the compounds are stable towards reductive elimination and do not react with the solvent. The conductivities in dimethylsulphoxide (DMSO) and N,N -dimethylformamide (DMF) indicate that there is some ion pairing. IR and mass spectral data are reported and discussed.

Synthesis and configurations of 2-methyl-1-organo-1-halo-1-telluracyclopentanes

Abstract Some new cyclic telluronium salts (C 5 H 10 TeRX: R = CH 3 , CH 3 Cl 3 , X = I; R = CH 2 Ph, X = Br) have been prepared by oxidative addition of alkyl halides to 2-methyl-1-telluracyclopentane. The cis / trans ratio in the product mixture was determined by 1 H NMR spectroscopy.

Synthesis and characterization of 2,4-disubstituted-5-imino-Δ2-1,3,4-telluradiazolines and 1,4-dihydro-2-imino-3-telluraquinolines

Abstract 2,4-Disubstituted-5-imino- Δ 2 -1,3,4,-telluradiazolines were isolated together with α-tellurocyanatobenzaldehyde arylhydrazones when potassium tellurocyanate was reacted with hydrazidoyl bromides in DMSO solution. N -Acetyl derivatives were prepared by reaction of 5-imino- δ 2 -1,3,4-teluradiazolines with acetic anhydride. Reaction of 2-amino-benzyl iodide with KTeCN afforded the novel heterocyclic tellurium compound, 1,4-dihydro-2-imino-3-telluraquinoline, which, on treatment with acetic anhydride, gave the acetyl derivative. The acetyl derivative was hydrolysed with HCl/H 2 O to afford 1- N -acetyl-4-hydro-3-telluraquinolin-2-one.

Charge-transfer complexes of 5,6-dimethyl,1,3-dihydro-2-telluraindene, with quinones

Abstract The new 5,6-dimethyl-1,3-dihydro-2-telluraindene was used as a donor to form 1:1 donor-acceptor complexes with p -benzoquinone, 1,4-naphthaquinone and 2,3-dimethylanthraquinone, respectively. Solid conductivity, UV-vis, IR, 1 H NMR, ESR and mass spectral data are discussed, and it is concluded that the degree of charge-transfer is small. The [C 10 H 12 Te] + dot [C 10 H 6 O 2 ] − dot complex shows evidence of semiconducting properties.

The thermal stability of some new cyclic tellurium compounds

The thermal stability of some new cyclic tellurium compounds, i.e., C4H8TeRX: R,X = I, I (1); CH3, I (2); C2H5, Br (3); C3H5, Cl (4); PhCOCH2, Br (5); 4-BrPhCOCH2, Br (6); Ph, BPh4(7); and C5H10TeRX: R, X = I, I (8); CH3, I (9), were studied by thermogravimetric analysis. Compounds 2 and 9 vaporised at 245 and 165°C, respectively. The other compounds decompose in three stages, losing RX in the first stage, then eliminating tellurium to form cyclobutane.