6-Methoxy- and 6-dimethylaminoazulenes with methylthio groups at the 1- or 1,3-positions have been prepared by electrophilic substitution of the corresponding azulenes with DMSO in the presence of acid anhydride, followed by treatment with Et3N. The products, 1-methylthioazulenes, reacted with Tf2O to afford the corresponding 1,1′-biazulene derivatives in moderate yields. The redox behavior of these azulene and 1,1′-biazulene derivatives was examined by cyclic voltammetry (CV), which revealed reversible electron transfers under electrochemical oxidation conditions. 6-Dimethylamino-1,3-bis(methylthio)azulenes with a heteroaiyl group at the 2-position were also prepared by the reaction of 6-dimethylamino-1,3- bis(methylthio)azulene with triflates of iV-containing heterocycles, i.e., pyridine, quinoline, isoquinoline, acridine, and 1,10-phenanthroline, followed by treatment with KOH in alcohols.
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