Photoinitiated azo‐hydrazo tautomerizm of 1‐p‐ toluenesulphonylazo‐2,4,6,8‐tetrakis (tert‐butyl)phenoxazine

Abstract

Abstract. A novel photochromic compound with NH−N intramolecular H-bond (1-p-toluenesulphonylazo-2,4,6,8-tetrakis(tert-butyl)phenoxazine) and the corresponding model structures (1-oxo-2,4,6,8-tetrakis(tertbutyl)phenoxazine, 2,4,5,7-tetrakis (tert-butyl )-1-( veratroylazo ) phenoxazine, 2,4,5,7-tetrakis ( tert-butyl )-Nacetyl-1-(p-toluenesulphonylazo)phenoxazine) have been synthesized and their spectral and photochemical properties are studied. The photochromic transformations observed are found to be conditioned by ESIPT (as a primary step) followed by E-Z isomerisation about N−N-bond.