Highly functionalized pyridines synthesis from N-sulfonyl ketimines and alkynes using the N-S bond as an internal oxidant.

The N-S bond-based internal oxidant offers a distinct approach for the synthesis of highly functionalized pyridines. A novel Rh(III)-catalyzed one-pot process undergoes an efficient C-C/C-N bond formation along with desulfonylation under very mild conditions. The method is quite simple, general, and efficient.