Palladium(II)‐Catalyzed Direct Arylations of Quinoxalin‐2(1H)‐ones with Arylsulfonyl Chlorides

Abstract A palladium‐catalyzed desulfitative coupling of quinoxalin‐2(1 H )‐ones with arylsulfonyl chlorides is described. C3‐Arylquinoxalin‐2(1 H )‐ones are readily accessible by reacting various arylsulfonyl chloride derivatives with quinoxalin‐2(1H)‐ones. The arylsulfonyl chloride undergoes palladium‐catalyzed C−S and S−Cl bond cleavage, which leads to direct desulfitative cross‐coupling with the quinoxalin‐2( H )‐one. Chloro‐ and fluoro‐aryl sulfonyl chlorides are successfully coupled with quinoxalin‐2(1 H )‐ones without carbon–halogen bond cleavage.