Recent developments and applications of Lewis acidic boron reagents

One field of organometallic chemistry that has seen great advancements over the last 20 years is that of main-group chemistry, in particular boron chemistry, that has led to a wealth of new discoveries. In this review, we will focus on modern advancements in this growing field, such as interesting uses of firmly established reagents, such as tris(pentafluorophenyl)borane, B(C₆F₅)₃, which has demonstrated extensive applications in a wide variety of chemistry. In addition to this, a number of novel Lewis acidic boranes and borocations have been recently synthesised, which are often structurally tailored for a specific role such as borylation reactions or use in main-group catalysis. The reactions of these compounds are broad in scope, inclusive of borylation substitution reactions, addition of B–E across π-bonds and applications in pharmaceuticals and materials science. In addition, boron reagents often constitute the Lewis acid moiety of frustrated Lewis pairs (FLPs), an area of main-group chemistry that has also expanded rapidly, with numerous applications notably in main-group catalysis. Newly discovered Lewis acidic boron reagents and their implementations are proving to be an appealing and exciting applications-based field as more advances are discovered.