GROUND AND EXCITED-STATE PROTON-TRANSFER OF 4-METHYL-2,6-DIACETYLPHENOL IN SOME HIGHLY POLAR APROTIC-SOLVENTS - INTERACTION WITH BASE

The proton transfer processes of the ground and excited states of 4-me thyl-2, 6-diacetylphenol (MAOH) have been investigated by means of abs orption, emission, nanosecond and picosecond transient emission spectr oscopy at different temperatures, The fluorescence quantum yields are found to be dependent on temperature, excitation energy and added base . Unlike 4-methyl-2, 6-diformylphenol (MFOH), MAOH shows a single fluo rescence band at room temperature in dimethyl sulphoxide and N,N-dimet hylformamide and at 77K it does not exhibit any phosphorescence emissi on. The fluorescence lifetime and decay rates of MAOH are temperature dependent and are relatively faster than those of MFOH. The solute-sol vent interaction appears to play an important role in. the proton tran sfer reaction of MAOH.