NHC–palladium(II) complex [Pd(μ–OH)Cl(IPr)}2] (IPr = bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) catalyzes the oxidativecoupling of a broad spectrum of aryl- and alkenylboronic acids at loadings down to 5 ppm. At the concentration of 0.05 mol% the catalyst permits an efficientreactionunderbase-freeconditions.