Aspects of intramolecular light energy and electron transfer will be discussed for three protein cofactor complexes, whose three-dimensional structures have been elucidated by X-ray crystallography: components of light-harvesting cyanobacterial phycobilisomes, the purple bacterial reaction centre and the blue multi-copper oxidases. A wealth of functional data is available for these systems whic...

Abstract Intramolecular charge transfer (ICT) is a fundamental mechanism that enables the development of numerous fluorophores and probes for bioimaging sensing. However, electron-withdrawing targets (EWTs)-induced fluorescence quenching long-standing unsolved issue in ICT fluorophores, significantly limits widespread applicability. Here we report simple generalizable structural-modification co...

Catalytic processes that form functionalized cyclic molecules represent a key transformation for synthetic organic chemistry. Recently, a number of organocatalytic processes have emerged that often provide excellent levels of both enantioand diastereocontrol for the synthesis of cyclic molecules. Our recent studies have identified the utility of ammonium ylides for carbon–carbon bond formation....

Electron transfer (ET) occurring in or after electronic excitation in flexibly bonded donor-acceptor (D-A) molecules are accompanied by structural relaxation. In singly bonded D-A molecules often the lltwistedff intramolecular charge transfer (TICT) structures are formed. Evidence for the TICT hypothesis is presented. In some compounds behaviour deviating from the original TICT model is observe...

this paper is a density functional theory (dft) calculation of intramolecular proton transfer (ipt) in 6-hydroxypicolinic acid (6hpa, 6-hydroxypyridine-2-carboxylic acid) tautomeric forms. the transition state for the enol-to-keto transition is reported in the gas phase and in four different solvents. the planar and non-planar dimer forms of 6hpa keto and enol, respectively, were also studied i...

Photophysics of 2-hydroxy-1-naphthaldehyde semicarbazone (2HNS) and the corresponding thiosemicarbazone (2HNT) are explored in n-heptane and methanol as solvents, focusing on the intramolecular proton transfer (IPT) in the ground (S0) and the first excited singlet (S1) states using absorption, steady state and time-resolved fluorometric techniques. The feasibility of the IPT process in the two ...

In this paper, the application of the double radical nucleophilic aromatic substitution (SRN1) in various dihalogenated, mostly diiodinated, π-conjugated systems as a tool for qualitatively estimating their π-conjugation is described. This approach uses electron delocalisation as a measure of π-conjugation. Electron injection into the π-system is achieved via reaction of an intermediate aryl ra...

A novel tris heteroleptic dipyridophenazine complex of ruthenium(II), [{Ru(phen)(dppz)(bpy'-his)}{Ru(NH3)5}]5+, containing a covalently tethered ruthenium pentammine quencher coordinated through a bridging histidine has been synthesized and characterized spectroscopically and biochemically in a DNA environment and in organic solvent. Steady-state and time-resolved luminescence measurements indi...

In this paper, the application of the double radical nucleophilic aromatic substitution (SRN1) in various dihalogenated, mostly diiodinated, p-conjugated systems as a tool for qualitatively estimating their pconjugation is described. This approach uses electron delocalisation as a measure of p-conjugation. Electron injection into the p-system is achieved via reaction of an intermediate aryl rad...