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

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.