Issue 9, 1988

2-Pyridyl- and quinolin-2-yl-functionalised organyltellurium ligands. The stabilisation of diorganyl tritellurides. The crystal and molecular structures of 2-(2-pyridyl)phenyltellurium(IV) tribromide, dimethyldithiocarbamato[2-(2-pyridyl)phenyl]tellurium(II), and p-ethoxyphenyl 2-(2-pyridyl)phenyl telluride

Abstract

The syntheses and spectroscopic data (13C n.m.r.) for some new organyltellurium ligands are described. Thus trans metallation of 2-(2-pyridyl)phenyl-(R) or 2-(quinolin-2-yl)phenyl-(R′) mercury(II) chloride with TeBr4 gives the organyltellurium tribromides RTeBr3 and R′TeBr3, which may be reduced to the organyltellurium bromides RTeBr and R′TeBr, some metathesis reactions of which are described; or, in the presence of excess hydrazine, to diorganyl ditellurides, R2Te2 and R′2Te2. Reduction of RTeBr3X with NaBH4 gave a novel tritelluride, R2Te3; a method of preparation for R′2Te3 was also devised. Syntheses of the tellurides R2Te, R′2Te, and RTe(C6H4OEt-p) were developed and the intermediacy of ionic compounds [R2TeBr][HgClBr2] and [R2TeCl][HgCl3] noted. The crystal structures of 2-(2-pyridyl)phenyltellurium(IV) tribromide, (1), dimethyldithiocarbamato [2-(2-pyridyl)phenyl]tellurium(II), (2), and p-ethoxyphenyl 2-(2-pyridyl)phenyltelluride, (3), have been determined from three-dimensional X-ray counter data. Complex (1) is triclinic, space group P[1 with combining macron] with a= 6.953(6), b= 8.382(1), c= 12.133(2)Å, α= 78.68(1), β= 82.87(4), γ= 87.14(4)°, and Z= 2; R= 0.0735 for 1 963 observed reflections. The co-ordination about Te is octahedral with a vacant equatorial position, two Br atoms apical, the third Br and the organic group equatorial [Te–C, 2.110(19); Te–N, 2.244(14)Å]. The compound is essentially monomeric, with a weak association between Te and Br [3.596(3)Å] in a neighbouring molecule. Complex (2) is triclinic, space group P[1 with combining macron] with a= 8.809(3), b= 9.032(5), c= 10.727(4)Å, α= 83.06(4), β= 86.49(3), γ= 63.68(4), and Z= 2; R= 0.0417 for 2 502 observed reflections. The co-ordination about Te is trigonal bipyramidal, C(1) and two lone pairs of Te comprising the equatorial co-ordination and the S(1) atom together with the pyridyl-N atom axial [Te–C, 2.111(5); Te–N, 2.354(4)Å]. No significant intermolecular contacts occur. Complex (3) is monoclinic, space group P21/c with a= 13.422(2), b= 16.469(3), c= 7.711(3)Å, β= 91.01(2)°, and Z= 4; R= 0.0415 for 2 014 observed reflections. The Te atom is bonded to two C atoms. The N atom of the pyridyl ring is twisted away from Te [Te–N, 2.695(4)Å] by rotation of the pyridyl ring about the pyridyl–phenyl bond by 23.2(3)°, a manifestation of the trans effect of the Te–C(ethoxyphenyl) covalent bond.

Article information

Article type
Paper

J. Chem. Soc., Dalton Trans., 1988, 2363-2371

2-Pyridyl- and quinolin-2-yl-functionalised organyltellurium ligands. The stabilisation of diorganyl tritellurides. The crystal and molecular structures of 2-(2-pyridyl)phenyltellurium(IV) tribromide, dimethyldithiocarbamato[2-(2-pyridyl)phenyl]tellurium(II), and p-ethoxyphenyl 2-(2-pyridyl)phenyl telluride

N. Al-Salim, A. A. West, W. R. McWhinnie and T. A. Hamor, J. Chem. Soc., Dalton Trans., 1988, 2363 DOI: 10.1039/DT9880002363

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements