“Novel Metal‐Free Porphyrin with Ionic Liquid and Sulphonic Acid Moieties for Visible Light Assisted Photocatalytic C−N Coupling of Heterocyclic Compounds with Aryl Halides”

Abstract Metal‐free Buchwald‐Hartwig type photocatalytic approach for N‐substitution of 1,2,4‐triazole at normal temperature was explored for the first‐time using novel imidazolium based Brønsted acid functionalized porphyrin (ImBAFPc). The energy band gap and Hammett acidity were determined by UV‐Vis spectrophotometer. The energy band gap, 1.06 eV supported absorption of radiation in the visible region. The N‐arylation of 1,2,4‐triazole with various Ar−X was achieved in a home‐made photoreactor by heterogeneous, recyclable ImBAFPc photocatalyst under irradiation of 5 W LED with good yields. The protocol tolerated electron donating and attracting Ar−X, including inactivated chlorobenzene, affording the arylated triazole with admirable yields. under ambient photocatalytic conditions.