Electrochemical properties of a disilene, a tetrasila-l,3-butadiene, and their germanium analogues

Annemarie Schäfer, Manfred Weidenbruch, Thomas Müller, Kendrekar Pravinkumar, James Y. Becker

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

The redox properties of arylsubstituted disuene (1), tetrasila-l,3- butadiene (2), digermene (3), and tetragerma-l,3-butadiene (4) (in which the aryl group is 2,4,6-triisopropylphenyl) have been studied by cyclic voltammetry (CV) in two different solvents. In odichlorobenzene, disuene 1 exhibited reversible redox couples in both oxidation and reduction processes, whereas tetrasilabutadiene 2 showed a reversible behavior only in its oxidation and an irreversible wave in its reduction. Tetragermabutadiene 4 afforded a reversible couple in its reduction and an irreversible wave in its oxidation, whereas digermene 3 showed only an irreversible oxidation wave but no reduction one. In comparison, all observed oxidation and reduction waves in THF were irreversible. In both solvents, the same trend of decreasing ease of oxidation has been observed: 2>4>3>1. The calculated vertical ionization energies (E i) for the 2,6-dimethylphenyl-substituted model compounds 9-12 afforded a trend of ease of oxidation that decreases in the series tetrasilabutadiene 10 > tetragermabuta-diene 12 > disilene 9 > digermene 11. This predicted trend parallels the measured oxidation potentials in the sense that the heavy butadienes are easier to oxidize than the heavy alkenes. The trend in the reduction direction has been found to be different in the two solvents studied. The computed electron affinities (Eea) for compounds 912 indicated that the ease of reduction decreased in the sequence tetragermabutadiene 12 > tetrasilabutadiene 10 > digermene 11 > disilene 9. However, no straightforward relation between the computed electron affinities and the experimentally measured reduction potentials has been found.

Original languageEnglish
Pages (from-to)8424-8428
Number of pages5
JournalChemistry - A European Journal
Volume15
Issue number34
DOIs
StatePublished - 24 Aug 2009

Keywords

  • Computer chemistry
  • Conjugation
  • Cyclic voltammetry
  • Germanium
  • Silicon

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Fingerprint

Dive into the research topics of 'Electrochemical properties of a disilene, a tetrasila-l,3-butadiene, and their germanium analogues'. Together they form a unique fingerprint.

Cite this