Allylic boron compounds have gained a prominent position as a truly practical class of synthetic reagents in the past twenty-five years. Their main application as a method for the stereoselective synthesis of homoallylic alcohols by allyl-transfer to carbonyl compounds is essentially unmatched. In this process, a new carbon-carbon bond is formed, and up to two new stereogenic centers are created in a predictably controlled manner. Highly effective and general enantioselective variants are available, with countless applications in the total syntheses of polyacetate and polypropionate...