Synthesis and structural study of 2-arylbenzotriazoles related to Tinuvins

Abstract A total number of nineteen 2-arylbenzotriazoles related to the UV absorber Tinuvin P have been studied. Moreover, besides those bearing a 2′-hydroxy substituent, known to experience ESIPT (Excited-State Intramolecular Proton Transfer), we have also prepared three compounds having another ortho -hydroxy group at position 6′. The X-ray molecular structures of five key representatives have been determined and some important features related to their behavior discussed on the basis of solution and solid-state NMR, as well as B3LYP/6-311++G(d,p) computational results.