2,3,8,9-Dibenzo-5,6-(substituted)benzo-1,4-dithio-7-azacyclonona-2,5,8- trienes. Synthesis and Mechanistic Study

Article abstract of DOI:10.1002/jhet.5570340101

5-(2-Acetamidoaryl)thianthreniumyl perchlorates reacted with potassium hydroxide in methanol at reflux giving 2,3,8,9-dibenzo-5,6-(substituted)benzo-1,4-dithio-7-azacyclonona-2,5,8-trienes 4 in 43 to 75% yields, whereas the reactions of the same compounds with sodium hydride in the absence or in the presence of dimethyl sulfate in refluxing tetrahydrofuran gave N-acetylated and N-methylated 4 in 68 to 96% and 27 to 56% yields, respectively. The mechanism of the formation of the products might be explained by a nucleophilic attack of amide ions 10, 12, and 14 at the ispo-position of the thianthrene ring. A sulfuranyl radical mechanism might be involved in these reactions.