Metal-Free Regioselective Direct Thiolation of 2-Pyridones

A highly regioselective metal-free direct C−H thiolation of 2-pyridones with disulfides/thiols has been developed. A combination of persulfate and a commercially available halide source such as LiCl, NCS or I2 enables the successful direct incorporation of a sulfide moiety into to the 5-position of pyridone under mild conditions, providing a useful and convenient approach for the preparation of a diverse array of 5-thio-substituted pyridones in moderate to excellent yields.