Carbon–carbon (C–C) bonds make up the skeletons of most organic molecules. The selective manipulation of C–C bonds offers a direct approach to editing molecular scaffolds but remains challenging. The kinetic inertness of C–C bonds can be overcome with transition-metal catalysis, which, nevertheless, relies on a substrate being highly strained or bearing a permanent directing group (DG). The driving force for C–C activation in these cases is strain relief and the formation of a stable metallocycle, respectively. Over the past two decades, a strategy has emerged that uses temporary or removable DGs to effect C–C activation of more common and less strained compounds. A variety of C–C bonds in less strained organic molecules are converted into more reactive transition-metal–carbon (M–C) bonds, enabling downstream transformations as part of diverse synthetic methods. This Review highlights catalytic approaches using temporary or removable DGs to help activate unstrained C–C bonds. The content is organized according to the temporary or removable nature of the DGs and includes applications in the synthesis of natural products or bioactive molecules.

碳-碳（C-C）键构成了大多数有机分子的骨架。C-C 键的选择性操作提供了编辑分子支架的直接方法，但仍然具有挑战性。C-C键的动力学惰性可以通过过渡金属催化来克服，然而，过渡金属催化依赖于高度应变或带有永久导向基团（DG）的基材。在这些情况下，C-C 活化的驱动力分别是应力消除和稳定金属环的形成。在过去的二十年中，出现了一种策略，使用临时或可移动的 DG 来实现更常见和张力较小的化合物的 C-C 激活。张力较小的有机分子中的各种 C-C 键被转化为更具反应性的过渡金属-碳 (M-C) 键，从而使下游转化成为多种合成方法的一部分。本综述重点介绍了使用临时或可移动 DG 来帮助激活无应变 C-C 键的催化方法。内容根据 DG 的临时或可移除性质进行组织，包括在天然产物或生物活性分子合成中的应用。