Skip to main content
eScholarship
Open Access Publications from the University of California

Halterman Corroles and Their Use as a Probe of the Conformational Dynamics of the Inherently Chiral Copper Corrole Chromophore.

  • Author(s): Thomas, Kolle E
  • McCormick, Laura J
  • Carrié, Daniel
  • Vazquez-Lima, Hugo
  • Simonneaux, Gérard
  • Ghosh, Abhik
  • et al.
Abstract

Halterman corroles have been synthesized for the first time from pyrrole and Halterman's aldehyde via Gryko's "water-methanol method". These were derivatized to the corresponding copper complexes and subsequently to the β-octabromo complexes. Electronic circular dichroism spectra were recorded for the enantiopure copper complexes, affording the first such measurements for the inherently chiral Cu corrole chromophore. Interestingly, for a given configuration of the Halterman substituents, X-ray crystallographic studies revealed both P and M conformations of the Cu-corrole core, proving that the substituents, even in conjunction with β-octabromination, are unable to lock the Cu-corrole core into a given chirality. The overall body of evidence strongly indicates a dynamic equilibrium between the P and M conformations. Such an interconversion, which presumably proceeds via saddling inversion, provides a rationale for our failure so far to resolve sterically hindered Cu corroles into their constituent enantiomers by means of chiral HPLC.

Main Content
Current View