Chiral C1-symmetric 2,2′:6′,2′′-terpyridine ligands: Synthesis, characterization, complexation with copper(II), rhodium(III) and ruthenium(II) ions and use of the complexes in catalytic cyclopropanation of styrene

Chi Tung Yeung, Wing Sze Lee, Chui Shan Tsang, Shek Man Yiu, Wing Tak Wong, Wai Yeung Wong, Hoi Lun Kwong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

22 Citations (Scopus)

Abstract

Three new optically pure C1-terpyridine ligands (L1-3) were prepared and the copper(II) complexes, of formula [Cu(L)Cl2], the rhodium(III) complexes, of formula [Rh(L)Cl3], and the ruthenium(II) complexes, of formula cis- or trans-[Ru(L)(X)Cl2] (X = DMSO or CO), were synthesized. Structures of a chiral C1-ligand, a copper complex, a rhodium complex and a ruthenium DMSO complex were analysed using X-ray crystal structure analysis. The copper, rhodium and ruthenium complexes were shown to be precursors of catalysts for cyclopropanation. Reaction of [Cu(L)Cl2], [Rh(L)Cl3] or cis- or trans-[Ru(L)(X)Cl2] with AgOTf converted the complex to catalyst, which in the case of trans-[Ru(L)(CO)Cl2] gave enantioselectivities of up to 67% ee for the cis-isomers of styrene cyclopropanes with t-butyl diazoacetate. Comparisons with C2-analog of copper, rhodium and ruthenium catalysts were made.
Original languageEnglish
Pages (from-to)1497-1507
Number of pages11
JournalPolyhedron
Volume29
Issue number5
DOIs
Publication statusPublished - 30 Mar 2010
Externally publishedYes

Keywords

  • Asymmetric catalysis
  • Chiral terpyridine
  • Copper
  • Metal-catalyzed cyclopropanation
  • Rhodium
  • Ruthenium

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Inorganic Chemistry
  • Materials Chemistry

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