Photochemical reactions of -2,4,6-trimethyl-1,3,5-trithiane in solution

The mechanism for the photoreaction of -2,4,6-trimethyl-1,3-5-trithiane ( - TMT) in acetonitrile was investigated using steady-state and laser flash ph otolysis. The main photoproducts were determined to be the thioester CH3C(= S)SCH(CH3)SCH2CH3 and the -TMT isomer. These products were identified by an alytical and spectroscopic methods. The quantum yield for -TMT disappearanc e was measured as Phi (-TMT) = 0.43, and quantum yields for the formation o f products were Phi (thioester) = 0.32 and Phi (-TMT) = 0.10. A short-lived ( = 13 s) intermediate was observed in the flash photolysis experiments th at was seen to decay into the thioester (the stable photoproduct). A detail ed mechanism of the primary and secondary processes was proposed and discus sed that accounts for the experimental results. (C) 2001 Elsevier Science B .V. All rights reserved.