Regioselectivity of the substitution for the nitro group in 2,4,6-trinitrobenzonitrile under the action of thiols. The synthesis of 4,6-dinitro derivatives of benzoannelated sulfur-containing heterocycles

Conditions for the regioselective substitution for a nitro group in the ortho-position in 2,4,6-trinitrobenzonitrile under the action of thiols (PhCH₂SH, HSCH₂CO₂Et or PhSH) in the presence of K₂CO₃ or KOH were found, and the intramolecular cyclization of the ortho-fragments –SX and –CN (X = Cl or CH₂CO₂Et) was performed to afford 3-chloro-4,6-dinitrobenzo[d]isothiazole and 3-amino- 2-ethoxycarbonyl-4,6-dinitrobenzo[b]thiophene, respectively.