We report a novel rhodium-catalyzed rearrangement involving N-substituted 2-thiopyridones and diazoesters. This reaction proceeds through the rhodium-catalyzed formation of sulfur ylides, followed by a direct C−N bond cleavage to achieve N-to-C 1,4-pyridyl migration. The protocol can be used to construct various thiopyridines possessing tetrasubstituted carbon stereocenters in moderate to excellent yields, which expands the transformation pattern of sulfur ylide intermediates in rearrangement reactions.2-Pyridyl thioethers are found in the cores of various biologically active molecules and agrochemicals (Figure 1). 1 These skeletons are conventionally prepared through the catalytic or noncatalytic substitution of the halides in ArX with an RS group 2 or a transition-metal-catalyzed (TM-catalyzed) cross-coupling reaction with a thiol 3 or In(SR) 3 . 4 Such protocols generally require organic halides and stoichiometric amounts of additives. TM-free nucleophilic aromatic substitution (S N Ar) reactions with thiols, 5 thiosulfate salts, 6 disulfides, 7 and PhSSiMe 3 8 have also been reported as preferable methods; however, these protocols mainly require stoichiometric oxidants, strong bases, or high temperatures (above 100 °C).