Sulfur Nitrides in Organic Chemistry. 18. Preparation and Reduction of Benzo[1,2-<i>c</i>:3,4-<i>c</i>′:5,6-<i>c</i>″]tris- and Benzo[1,2-<i>c</i>:3,4-<i>c</i>′]bis[1,2,5]thiadiazole. A Convenient Route to Benzenehexamine and 1,2,3,4-Benzenetetramine
Benzotris- (3) and benzobis[1,2,5]thiadiazole (4) were prepared in a moderate yield, respectively, by the reaction of tetrasulfur tetranitride (5) with halocatechols (6) and -resorcinols (7). The reduction of 3 and 4 with Sn powder in a mixture of concentrated hydrochloric acid and dioxane gave benzenehexamine (1) and 1,2,3,4-benzenetetramine (2a) and its 5-methyl derivative (2b) in good yields, as