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Phenylene-bridged bis(benzimidazolium) (BBIm²⁺): a dicationic organic photoredox catalyst.

ABSTRACT: A dicationic photoredox catalyst composed of phenylene-bridged bis(benzimidazolium) (BBIm²⁺) was designed, synthesised and demonstrated to promote the photochemical decarboxylative hydroxylation and dimerisation of carboxylic acids. The catalytic activity of BBIm²⁺ was higher than that for a monocation analogue, suggesting that the dicationic nature of BBIm²⁺ plays a key role in these decarboxylative reactions. The rate constant for the decay of the triplet-triplet absorption of the excited BBIm²⁺ increased with increasing concentration of the carboxylate anion with a saturated dependence, suggesting that photoinduced electron transfer occurs within the ion pair complex composed of the triplet excited state of BBIm²⁺ and a carboxylate anion.

SUBMITTER: Kodama T

PROVIDER: S-EPMC8162872 | biostudies-literature |

REPOSITORIES: biostudies-literature

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