Synthesis of Sulfones
In a palladium catalyzed Negishi-type α-arylation of sulfones and sulfonamides with a broad range of aryl bromides, the substrates are selectively metalated in situ with tmp·ZnCl·LiCl base and cross-coupled in the presence of a catalyst system that is generated from Pd(dba)2 and XPhos.
T. Knauber, J. Tucker, J. Org. Chem., 2016, 81, 5636-5648.
Ni-catalyzed stereoconvergent Negishi arylations and alkenylations of racemic α-bromosulfonamides and -sulfones furnish cross-coupling product in very good ee and yield for an array of reaction partners. Mechanistic studies are consistent with the generation of a radical intermediate.
J. Choi, P. Martín-Gago, G. C. Fu, J. Am. Chem. Soc., 2014, 136, 12161-12165.