Chemistry of Oligopyrrolic Macrocycles: From Supramolecular Anion Recognition to Proton-Coupled Redox Reaction
소속 :
연사 : Prof. Chang-Hee Lee ( Kangwon National Univ )
일시 : 2013-04-11 16:30 ~
장소 : 500동 목암홀
일 시 : 2013년 4월 11일, 4:30 PM
장 소 : 500동 목암홀
-Abstract-
Development of molecular receptors possessing high affinity and selectivity for various
analytes are still an ongoing challenge in supramolecular chemistry. As results, many model systems utilizing various molecular scaffolds have been developed. Among them, calix[4] pyrroles have been shown to bind anions in organic polar media and the encapsulation of the binding domain of the calix[4]pyrrole greatly enhances the binding affinity. We have designed and synthesized various calix[4]pyrrole-based ion/molecular receptors. The guest binding studies indicated that the synthesized systems have shown many interesting roperties. Also, picket calix[4]pyrroles have been synthesized and studied for selective recognition of anions through fluorescent dye displacement assay (FDDA). The nano-hybrid of these receptor displayed even greater sensitivity and cationic calix[4]pyrrole displayed preferential selectivity for pyrophosphate and all other anions. The second topic will be a ‘proton-coupled electron transfer (PCET) processes’ which are among the most important phenomena that serve to control a variety of chemical and biological transformations. While extensively studied in a variety of natural systems and a number of discrete metal complexes, PCET mechanisms are less well codified in the case of purely organic compounds. We found that a planar, a 24 π-electron antiaromatic naphthorosarin displays unique redox reactivity upon protonation.
Specifically, treatment with acid (i.e., HI) yields a 26 π-electron aromatic triprotonated mono cationic species; it is produced spontaneously via an intermediate, but stable, 25 π-electron nonaromatic triprotonated mono radical dication.
장 소 : 500동 목암홀
-Abstract-
Development of molecular receptors possessing high affinity and selectivity for various
analytes are still an ongoing challenge in supramolecular chemistry. As results, many model systems utilizing various molecular scaffolds have been developed. Among them, calix[4] pyrroles have been shown to bind anions in organic polar media and the encapsulation of the binding domain of the calix[4]pyrrole greatly enhances the binding affinity. We have designed and synthesized various calix[4]pyrrole-based ion/molecular receptors. The guest binding studies indicated that the synthesized systems have shown many interesting roperties. Also, picket calix[4]pyrroles have been synthesized and studied for selective recognition of anions through fluorescent dye displacement assay (FDDA). The nano-hybrid of these receptor displayed even greater sensitivity and cationic calix[4]pyrrole displayed preferential selectivity for pyrophosphate and all other anions. The second topic will be a ‘proton-coupled electron transfer (PCET) processes’ which are among the most important phenomena that serve to control a variety of chemical and biological transformations. While extensively studied in a variety of natural systems and a number of discrete metal complexes, PCET mechanisms are less well codified in the case of purely organic compounds. We found that a planar, a 24 π-electron antiaromatic naphthorosarin displays unique redox reactivity upon protonation.
Specifically, treatment with acid (i.e., HI) yields a 26 π-electron aromatic triprotonated mono cationic species; it is produced spontaneously via an intermediate, but stable, 25 π-electron nonaromatic triprotonated mono radical dication.
