An efficient aromatization of 2-amino-4,5,6,7-tetrahydrobenzo-[b]thiophene-3-carboxylates in dimethyl sulfoxide catalyzed by p-toluenesulfonic acid was written by Adib, Mehdi;Soheilizad, Mehd;Rajai-daryasaraei, Saideh;Mirzaei, Peiman. And the article was included in Synlett in 2015.Application In Synthesis of Ethyl 2-amino-4-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate The following contents are mentioned in the article:
An oxidation-aromatization of alkyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylates, is reported. The Gewald product, obtained from three-component condensation reaction between a cyclohexanone, an alkyl cyanoacetate, and sulfur, underwent an oxidation reaction in DMSO in the presence of a catalytic amount of p-toluenesulfonic acid to give the corresponding alkyl 2-aminobenzo[b]thiophene-3-carboxylate, e.g., I, in excellent yield. This study involved multiple reactions and reactants, such as Ethyl 2-amino-4-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (cas: 95211-67-9Application In Synthesis of Ethyl 2-amino-4-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate).
Ethyl 2-amino-4-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (cas: 95211-67-9) belongs to benzothiophene derivatives. Benzothiophene is relatively a stable molecule. The electrophilic substitution of benzothiophene systems is much less regioselective than that of indoles. It is found within the chemical structures of pharmaceutical drugs such as zileuton, raloxifene, and sertaconazole, and also BTCP.Application In Synthesis of Ethyl 2-amino-4-methyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate
Referemce:
Benzothiophene – Wikipedia,
Benzothiophene | C8H6S – PubChem