Regioselective transition metal- and halogen-free direct dithiolation at C(sp3)–H of nitrotoluenes with diaryl disulfides

Abstract

Here we describe a potassium tert-butoxide-mediated regioselective direct C–S bond formation at the C(sp³)–H position of nitrotoluenes with disulfides in DMSO at room temperature. The developed reaction generated, in good yields, various dithioacetals having OMe, halogen, and NH₂ functionalities at various positions of the arene rings of the disulfides. Interestingly, in the absence of nitrotoluene, diaryl disulfides and diselenides underwent one-carbon homologation to form dithioacetals and diselenoacetals. Synthesized dithioacetals were transformed into 4-nitrobenzaldehyde and 7-(bis(phenylthio)methyl)-1H-indole.