Cooperative H 2 Activation by Borane‐Derived Frustrated Lewis Pairs

The coexistence of a strong Lewis acid and a Lewis base in solution, the so-called frustrated Lewis pairs, has led to the discovery of the metal-free hydrogen activation. From then on, this observation has inspired all kinds of chemists to develop more examples. The metal-free hydrogenation has been the so far most studied application of frustrated Lewis pair chemistry, and highly efficient methodologies for a number of unsaturated substrates have been developed. This chapter starts with a brief introduction to frustrated Lewis pair chemistry. The second and third parts discuss the mechanism of the hydrogen activation and the influence of the nature of the Lewis acid and the Lewis base on this process. These factors do not only influence the hydrogen activation but also have severe impact on catalytic transformations. These features are exemplified in the fourth part of the chapter by the discussion of frustrated Lewis pair-catalyzed hydrogenations of a number of substrate classes.