Following pioneering work by Bolm and co-workers,[1] B–Zn transmetallation reactions between arylboronic acids and diethylzinc have been exploited in a range of asymmetric nucleophilic addition reactions to carbonyl and related compounds in the presence of catalytic amounts of chiral ligands and, in some cases, transition-metal catalysts.[2–7] These reactions usually require a pre-activation step, in which ArB (OH) 2 and Et2Zn are heated ...
