Chemistry

Research project: Reid: Multidentate and macrocyclic organoselenium and -tellurium ligands

We are developing new synthetic routes for Se and Te macrocycles via high dilution methods and investigating their chemistry with TM and main group element acceptors to establish how the ligand architecture influences the structural characteristics and bonding in these species.

Currently Active: Yes

Project Overview

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Our previous studies provided evidence for increased ETM -donation in low valent species on descending Group 16. We are now exploring these and related ligands with alkyl Pt(0), (II) and (IV), Rh(I) and Ir(I) species, including oxidative addition and reductive elimination reactions. Synthesis of selenoether complexes of Ti(IV), Zr(IV) and Hf(IV), including both the 6-coordinate (distorted octahedral [MCl4{MeSe(CH2)2SeMe}] and the 8-coordinate (flattened dodecahedral) [MCl4{MeSe(CH2)2SeMe}2] (M = Zr, Hf).

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Development of new macrocyclic and polydentate telluroether compounds including MeC(CH2TePh)3and the first linear tritelluroethers, RTe(CH2)3Te(CH2)3TeR (R = Me or Ph), in which the Te atoms are (for the first time) introduced stepwise, and the first examples of mixed S/Te-donor macrocycles and O/Te macrocycles with various ring-sizes. Remarkably high (often essentially quantitative) yields of a new series of tridentate Se2O and Se2N(pyridyl) and also very rare Se3macrocycles with varying ring sizes and backbone structures have been achieved very recently via high dilution reactions.

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In a collaborative project with Prof. W. Levason and Dr A.L. Hector (Southampton) and Prof. I. Parkin and Dr C. Carmalt (UCL) we are also investigating the chemistry of early transition metal ions with selenolate and tellurolate ligands. The aims are to examine these as single source precursors for early transition metal selenide and telluride thin films and to evaluate these films as gas sensors. Selenoether and selenide (RSe) complexes of Ti, Zr, Hf, V and Nb are being investigated as CVD precursors to MSe2films. This approach provides complexes suitable as single source precursors allowing deposition of TiE2­, SnE2and SnE (E = S or Se) from neutral chalcogenoether complexes such as [SnCl4(Et2Se)2] and [MCl4{o-C6H4(CH2EMe)2}]. Also we have achieved the first CVD of ZrSe2thin films and hitherto unknown selenides, such as HfSe2via molecular selenolate precursors.

  • Synthesis, properties and ligating properties of the First Two Linear Tritelluroethers, Te(CH2CH2CH2TeR)2 (R = Me or Ph).
    A.J. Barton, W. Levason, G. Reid and A.J. Ward, Organometallics, 2001, 20, 3644.
  • Synthesis, properties and ligating properties of the First Two Linear Tritelluroethers, Te(CH2CH2CH2TeR)2 (R = Me or Ph).
    A.J. Barton, W. Levason, G. Reid and A.J. Ward, Organometallics, 2001, 20, 3644.
  • Ditelluroether Complexes of Manganese and Rhenium Carbonyl Halides: Synthesis, IR and Multinuclear NMR Spectroscopic and Structural Studies. A Comparison of the Bonding Properties of Dithio-, Diseleno- and Ditelluro-ethers in Low Valent Carbonyl Systems.
    W. Levason, S.D. Orchard and G. Reid, Organometallics., 1999, 18, 1275.
  • Synthesis, characterisation and coordinating properties of the small ring S2Te-donor macrocycles [9]aneS2Te (1,4-dithia-7-telluracyclononane), [11]aneS2Te (1,4-dithia-8-telluracycloundecane) and [12]aneS2Te (1,5-dithia-9-telluracyclododecane)
    M.J. Hesford, W. Levason, M.L. Matthews, S.D. Orchard and G. Reid, Dalton Trans., 2003, 2434.
  • Synthesis and complexation of the mixed tellurium-oxygen macrocycles 1-tellura-4,7-dioxacyclononane, [9]aneO2Te and 1,10-ditellura-4,7,10,13-tetraoxacyclooctadecane, [18]aneO4Te2.
    M.J. Hesford, W. Levason, M.L. Matthews and G. Reid, Dalton Trans., 2003, 2852.
  • Synthesis and Properties of Organometallic Pt(II) and Pt(IV) Complexes With Polydentate Seleno- and Telluro-ethers and Macrocyclic Selenoethers
    W. Levason, J. M. Manning, P. Pawelzyk and G. Reid, Eur. J. Inorg. Chem., 2006, 4380-4390.
  • Studies on Transition Metal Complexes with the Wide Angle Xylyl Dithio-, Diseleno- and Ditelluroethers, o-C6H4(CH2EMe)2
    W. Levason, M. Nirwan, R. Ratnani, G. Reid, N. Tsoureas and M. Webster, Dalton Trans., 2007, 439-448.
  • Selenoether macrocyclic chemistry ? syntheses and properties of new tridentate and hexadentate Se/O-donor macrocycles.
    W. Levason, J.M. Manning, M. Nirwan, R. Ratnani, G. Reid, H.L. Smith, M. Webster, Dalton Trans., 2008, in press.
  • Thio- and seleno-ether complexes with Group 4 tetrahalides and tin tetrachloride: preparation and use in CVD for metal chalcogenide films
    S. D. Reid, A. L. Hector, W. Levason, G. Reid, B. J. Waller and M. Webster, Dalton Trans., 2007, 4769-4777

Staff

Members of staff associated with this project: