Abstract: In this work sphenyl 1-thionapthoate and 2-benzoylthiobenzothiazole were synthesized and their pbotochemical and photophysical behavior were studied.Due to introductionof naphthyl and benzothiazolyl group,the absorption range of these compounds have beenefficiently broadened.It was discovered in this work that the intensity of sphenyl 1-thion-aphthoate increased with time interval of irradiation,which was because of production of α,α'-binaphthyl with high fluorescence quantum yield.However,the phenomenon could notbe observed in photolysis of 2-benzoylthiobenzothiazole.Cage effect and external magneticfield effect also were discussed in this paper.

Key words: photoinitiator, photolysis, external magnetic field To whom correspondence should be addressed.