Abstract
An efficient Ni-catalyzed, Mn-mediated denitrogenative cross-electrophile coupling of N-alkyl-1,2,3-benzotriazinones with alkyl tosylates and mesylates for access to o-alkyl secondary benzamides is reported. The method uses inexpensive non-anhydrous dimethyl acetamide (DMA) in combination with tetrabutyl ammonium iodide (TBAI) as a co-catalyst to convert sulfonates into iodides in situ. Scope and limitations of the protocol have been demonstrated by >30 examples with yields up to 91%, showing a large electronic effect from the N-substituent in benzotriazinones. An unexpected steric acceleration has been observed from the core of benzotriazinones, not only promising a highly efficient access to 2-alkyl-2,3-disubstituted benzamides but also shedding light on the rate-limiting steps in the catalytic cycle.