Synthesis of ortho-Methylated Benzamides via Palladium-Catalyzed Denitrogenative Cross-Coupling Reaction of [1,2,3]-Benzotriazin-4(3H)-ones with DABAL-Me₃

We herein developed a palladium-catalyzed reaction of[1,2,3]-benzotriazin-4(3H)-ones with DABAL-Me-3 [bis(trimethylaluminum)-1,4-diazabicyclo[2.2.2]octaneadduct], a cheap, stable, and solid organoaluminum reagent. In thepresence of Pd(OAc)(2)/XantPhos as a commercially availablecatalyst, [1,2,3]-benzotriazin-4(3H)-ones underwentdenitrogenative coupling with DABAL-Me-3 to afford a widearray of N-aryl amides derived from ortho-methylated carboxylic acids. Under the same catalytic conditions, ortho-ethylation of [1,2,3]-benzotriazin-4(3H)-ones could also be achieved by using triethylaluminum.