67820-08-0Relevant articles and documents
Recognition of imidazoles by strapped zinc(II) porphyrin receptors: Insight into the induced-fit mechanism
Brandel, Jeremy,Trabolsi, Ali,Melin, Frederic,Elhabiri, Mourad,Weiss, Jean,Albrecht-Gary, Anne-Marie
, p. 9534 - 9536 (2007)
Imidazole-porphyrin coordination has become an important tool in the design of self-assembled materials. A combination of spectrophotometric and stopped-flow techniques has been used to gain insight into the control of imidazole binding in the distal pocket of phenanthroline-strapped porphyrins. The binding studies of a variety of imidazole substrates in combination with both hindered and accessible receptors have permitted the determination of the thermodynamic and kinetic parameters associated with the imidazole binding.
Molecular tools for the self-assembly of bisporphyrin photodyads: A comprehensive physicochemical and photophysical study
Brandel, Jeremy,Trabolsi, Ali,Traboulsi, Hassan,Melin, Frederic,Koepf, Matthieu,Wytko, Jennifer A.,Elhabiri, Mourad,Weiss, Jean,Albrecht-Gary, Anne-Marie
, p. 3743 - 3754 (2009/09/26)
Accessible and hindered phenanthroline-strapped Zn(II) porphyrin receptors exhibited suitable topography tailored to strongly and selectively bind N 1-unsubstituted imidazoles and imidazoles appended to free-base porphyrins. Distal binding was
Reactions of metalloporphyrin π radicals. 1. Complexation of zinc tetraphenylporphyrin cation and anion radicals with nitrogenous bases
Kadish,Shiue,Rhodes,Bottomley
, p. 1274 - 1277 (2008/10/08)
Stability constants for TPPZn with 20 nitrogenous bases were obtained by the method of proportional absorbances. These results were combined with electrochemical data to obtain stability constants for the reaction of TPPZn radical cations and radical anions with ligands. Values of log β1 ranged from 1.64 to 4.59 for ligand addition to [TPPZn]+ and from 1.47 to 3.50 for addition to [TPPZn]-. Only five-coordinate complexes were observed. These measurements represented the first values of stability constants obtained for nitrogeneous base addition to porphyrin π radicals. The changes in stability constants observed as a function of ligand pKa allowed the tuning of the zinc radical cation half-wave potential between 0.83 and 0.74 (vs. SCE) and the radical anion potential between -1.38 and -1.49 V. The ligand additions proceeded in a chemically reversible fashion over the experimental time frame. Thin-layer spectra for oxidations showed slight spectral differences between [TPPZn]+ and [TPPZn(L)]+ but were almost totally insensitive to a specific L. The possibility of an alternate oxidative pathway to the β-substituted pyrrole product was examined and found not to be operative for this time frame and solvent system.
