Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K.
J Am Chem Soc. 2022 Oct 12;144(40):18195-18211. doi: 10.1021/jacs.2c08752. Epub 2022 Sep 30.
Electrostatic attraction between two groups of opposite charge, typically known as ion-pairing, offers unique opportunities for the design of systems to enable selectivity control in chemical reactions. Catalysis using noncovalent interactions is an established and vibrant research area, but it is noticeable that hydrogen bonding interactions are still the main interaction of choice in system design. Opposite charges experience the powerful force of Coulombic attraction and have the ability to exert fundamental influence on the outcome of reactions that involve charged reagents, intermediates or catalysts. In this Perspective, we will examine how ion-pairing interactions have been used to control selectivity in C-H bond functionalization processes. This broad class of reactions provides an interesting and thought-provoking lens through which to examine the application of ion-pairing design strategies because it is one that encompasses great mechanistic diversity, poses significant selectivity challenges, and perhaps most importantly is of immense interest to synthetic chemists in both industry and academia. We survey reactions that proceed via radical and ionic mechanisms alongside those that involve transition metal catalysis and will deal with control of site-selectivity and enantioselectivity. We anticipate that as this emerging area develops, it will become an ever-more important design strategy for selectivity control.
两组相反电荷之间的静电吸引，通常称为离子配对，为设计能够在化学反应中实现选择性控制的系统提供了独特的机会。利用非共价相互作用的催化是一个既定的、充满活力的研究领域，但值得注意的是，氢键相互作用仍然是系统设计中主要选择的相互作用。相反电荷会经历库仑吸引力的强大力量，并且能够对涉及带电试剂、中间体或催化剂的反应的结果产生根本影响。在本观点中，我们将研究离子配对相互作用如何用于控制 C-H 键官能化过程中的选择性。这类广泛的反应提供了一个有趣且发人深省的视角，可以通过它来检验离子配对设计策略的应用，因为它涵盖了很大的机械多样性，带来了重大的选择性挑战，也许最重要的是，它引起了工业界和学术界的合成化学家的极大兴趣。我们调查了通过自由基和离子机制进行的反应，以及涉及过渡金属催化的反应，并将涉及对位点选择性和对映选择性的控制。我们预计，随着这个新兴领域的发展，它将成为选择性控制的一个越来越重要的设计策略。
