Chiral atropisomeric 2-iodo-4,4′,6,6′-tetramethyl-2′- (diphenylphosphoryl)-1,1′-biphenyl-enantiodifferentiation by Rh 2[MTPA]4-adduct formation and conformational analysis

Stefan Moeller, Dieter Albert, Helmut Duddeck, András Simon, Gábor Tóth, Oleg M. Demchuk, K. Michał Pietrusiewicz

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2 Citations (Scopus)


Enantiodifferentiation of the chiral 2-iodo-4,4′,6,6′- tetramethyl-2′-(diphenylphosphoryl)-1,1′-biphenyl (2) can be accomplished easily by adding one mole equivalent of the enantiopure dirhodium complex Rh(II)2[(R)-(+)-MTPA]4 (Rh*). The internal competition of the two bindings sites in 2, the Ph2P=O group, and the iodine atom was identified by variable-temperature 31P NMR. Energy optimization (PM3) and ROESY spectroscopy of 2 in the absence and presence of Rh* reveal that 2 prefers a conformation in the adducts, which is the least stable one in the free molecule, i.e., adduct formation is accompanied by a rotation of the Ph2P=O group about the C-2′-P bond.

Original languageEnglish
Pages (from-to)351-361
Number of pages11
JournalPhosphorus, Sulfur and Silicon and the Related Elements
Issue number2
Publication statusPublished - Feb 1 2006



  • Atropisomerism
  • Biphenyl
  • Chiral recognition
  • Conformational analysis
  • Dirhodium tetracarboxylate complex
  • Variable-temperature NMR

ASJC Scopus subject areas

  • Biochemistry
  • Organic Chemistry
  • Inorganic Chemistry

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