Impact of Transition-State Aromaticity on Selective Radical-Radical Coupling of Triarylimidazolyl Radicals.

ABSTRACT: Radical coupling reactions are generally known to have a low selectivity due to the high reactivity of radicals. In this study, high regio and substrate selectivity was discovered in the dimerization of triarylimidazolyl radicals (TAIR), a versatile photochromic reaction. When two different radicals, 2-(4-cyanophenyl)-4,5-diphenyl-1H-imidazolyl radical (CN-TAIR) and 2-(4-methoxyphenyl)-4,5-diphenyl-1H-imidazolyl radical (OMe-TAIR), were simultaneously generated in situ, a hexaarylbiimidazole, formed by selective coupling at the nitrogen atom at position 1 of CN-TAIR and the carbon atom at position 2 of OMe-TAIR, was isolated with high selectivity as the main product among 24 possible radical dimer hexaarylbiimidazole derivatives. This high r

SUBMITTER: Okamoto K 

PROVIDER: S-EPMC11760180 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature