Photolytic desulfurization and ring-contraction reactions of diethyl benzotrithiole and tetraethyl dibenzotetrathiocin proceeded without a desulfurization reagent such as trialkyl phosphite by irradiation with a 100 W high-pressure Hg lamp in CH2Cl2under Ar to produce tetraethyl thianthrene. By means of the photolysis, the thianthrene derivatives bearing trithiole and dithian rings on both sides of thianthrene were obtained in good yields. (C) 2000 Elsevier Science Ltd.
Kimura, T., Tsujimura, K., Mizusawa, S., Ito, S., Kawai, Y., Ogawa, S., & Sato, R. (2000). Photolytic preparation, structure, and electrochemical properties of thianthrene derivatives bearing trithiole and dithian rings. Tetrahedron Letters, 41(11), 1801–1805. https://doi.org/10.1016/S0040-4039(00)00033-2