A new one-pot synthesis of thieno[2,3-b]indole ring systems is described. Condensation of cyclohexyl isocyanide with indolin-2-thiones yielded 3-cyclohexyaminomethylene-indolin-2-thiones, which upon reaction with α-halocarbonyl compounds produced the title compounds.
A simple and effective method has been elaborated for the synthesis of thieno[2,3- B]indole ringsystem. It is based on the electrophilic recyclization of 2-alkyl-5-(2-isothiocyanoaryl)furans in the presence of anhydrous AlCl 3 .