Denitrogenative Suzuki-Miyaura Cross-coupling Reactions of benzotriazoles

Tang et al. have reported a denitrogenative Suzuki-Miyaura cross-coupling reaction from 1-(trifluoromethanesulfonyl)-1H-benzotriazoles (1). N-triflatebenzotriazoles (1) proceed through palladium-catalyzed cross-couplings with arly/vinyl boronic acids in the presence of AgBF₄ to afford ortho-substituted analine derivatives in good yield. Additionally, CO can be added to the reaction conditions to give ortho-acylated analines. The N-triflate and AgBF₄ are essential to the reactivity. They proposed that the AgBF₄ first coordinates with the electro deficient triazole facilitating ring opening to generate the arenediazonium intermediate 2, thereby both activating the resulting diazo group for oxidative insertion and stabilizing the overall structure. This unusual intermediate was proposed and supported by computational and experimental (¹H NMR) evidence.