A Greek cross dodecaphenylene

Sparteine-mediated asymmetric synthesis of chiral D2-symmetric π-conjugated tetra-o-phenylenes

Andrzej Rajca, Hua Wang, Pavel Bolshov, Suchada Rajca

Research output: Contribution to journalArticle

46 Citations (Scopus)

Abstract

The asymmetric synthesis of a chiral, nonracemic π-conjugated system with D2 point group of symmetry, dodecaphenylene 4 is described. In the key step, (-)-sparteine- and Cu(II)-mediated oxidation of 2,2′-dilithio-1,1′-biaryls in ether gives the corresponding dimers, tetra-o-phenylenes, in 80% isolated yields and 50-60% ee's. X-Ray crystallography confirms the structure of rac-4 and its molecular shape of a Greek cross. The torsional angles between the benzene rings in the tetra-o-phenylene core of rac-4 are in the 56.5-71.0° range. However, CD and UV spectra of 4 in CH2Cl2 are consistent with significant conjugation between the four terphenyl moieties.

Original languageEnglish (US)
Pages (from-to)3725-3735
Number of pages11
JournalTetrahedron
Volume57
Issue number17
DOIs
StatePublished - Apr 23 2001

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Sparteine
Point groups
X ray crystallography
X Ray Crystallography
Crystal symmetry
Benzene
Dimers
Ether
Oxidation

Keywords

  • Asymmetric synthesis
  • Biaryl
  • Chiral
  • Sparteine
  • π-conjugated

ASJC Scopus subject areas

  • Biochemistry
  • Drug Discovery
  • Organic Chemistry

Cite this

A Greek cross dodecaphenylene : Sparteine-mediated asymmetric synthesis of chiral D2-symmetric π-conjugated tetra-o-phenylenes. / Rajca, Andrzej; Wang, Hua; Bolshov, Pavel; Rajca, Suchada.

In: Tetrahedron, Vol. 57, No. 17, 23.04.2001, p. 3725-3735.

Research output: Contribution to journalArticle

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