Scope of the Two-Step, One-Pot Palladium-Catalyzed Borylation/Suzuki Cross-Coupling Reaction Utilizing Bis-Boronic Acid

The use of bis-boronic acid for the direct synthesis of boronic acids has greatly facilitated the two-step, one-pot borylation/Suzuki cross-coupling reaction between aryl and heteroaryl halides. With use of Buchwald’s second-generation XPhos preformed catalyst, high yields of cross-coupled products were obtained for most substrates. The method also allows an efficient two-step, one-pot synthesis, providing access to three distinct cross-coupled products after column chromatography. The method also provides a rapid and convenient route to teraryl compounds

Palladium-Catalyzed Borylation of Aryl and Heteroaryl Halides Utilizing Tetrakis(dimethylamino)diboron: One Step Greener

The palladium-catalyzed borylation of aryl and heteroaryl halides with a novel borylating agent, tetrakis(dimethylamino)diboron [(Me₂N)₂B–B(NMe₂)₂], is reported. The method is complementary to the previously reported method utilizing bis-boronic acid (BBA) in that certain substrates perform better under one set of optimized reaction conditions than the other. Because tetrakis(dimethylamino)diboron is the synthetic precursor to both BBA and bis(pinacolato)diboron (B₂Pin₂), the new method represents a more atom-economical and efficient approach to current borylation methods