The three isomeric naphthothietes 5, 11, and 16 were prepared according to the reaction sequences shown in Schemes 1-3. The final step was in each case a flash vacuum pyrolysis (FVP) of the corresconding mercaptonaphthalenemethanol4, 9, and 15, respectively. The thiete rings in 5 and 11 can be opened by gentle heating; the ring opening of the isomer 16 possesses a much higher activation barrier. A MNDO calculation of the AHf values of 5, 11 ...
