Synthesis and Some Reactions of 2-(Thien-2-yl)naphtho[1,2-<i>d</i>]tiazole
Condensation of 1-aminonaphthalene with thiophene-2-carbonyl chloride in 2-propanol furnished N -(1-naphthyl)- thiophene-2-carboxamide, the treatment of which with an excess of P2S5 in anhydrous pyridine led to the corresponding thioamide. Oxidation of the latter with potassium ferricyanide in an alkaline medium according to the Jacobson method yielded 2-(thien-2-yl)naphtho[1,2- d ]thiazole. The later was introduced into the electrophilic substitution reactions: nitration, bromination, formylation, and acylation. The reactions occurs exclusively at the position 5 of the thiophene ring.