Ground and excited-state intramolecular proton transfer in 3,5-dibromosalicylic acid

GABRIELA IBAÑEZ; GUILLERMO LABADIE; GRACIELA ESCANDAR; ALEJANDRO OLIVIERI

JOURNAL OF MOLECULAR STRUCTURE

Elsevier

Lugar: Asterdam; Año: 2003 vol. 645 p. 61 - 68

0022-2860

Abstract The existence of both ground- and excited-state proton transfer equilibrium between the enolic and keto tautomers of 3,5- dibromosalicylic acid has been investigated in aqueous solution using electronic absorption and luminescence emission spectroscopies, together with ab initio and semiempirical MO/CI calculations. The compound provides an example of a room temperature phosphorescence triplet-state emission from a phototautomer (ketonic) form. The interference from radiationless paths, which may in principle avoid the observation of the phosphorescence signal, was overcome by using a protective micellar medium and the presence of an external heavy atom. Keywords: Luminescence; Intramolecular proton transfer; MO calculations; 3,5-Dibromosalicylic acidLuminescence; Intramolecular proton transfer; MO calculations; 3,5-Dibromosalicylic acid