Jamagne Romain, Power Martin J, Zhang Zhi-Hui, Zango Germán, Gibber Benjamin, Leigh David A
Department of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK.
School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, P. R. China.
Chem Soc Rev. 2024 Oct 14;53(20):10216-10252. doi: 10.1039/d4cs00430b.
The active template synthesis of mechanically interlocked molecular architectures exploits the dual ability of various structural elements (metals or, in the case of metal-free active template synthesis, particular arrangements of functional groups) to serve as both a template for the organisation of building blocks and as a catalyst to facilitate the formation of covalent bonds between them. This enables the entwined or threaded intermediate structure to be covalently captured under kinetic control. Unlike classical passive template synthesis, the intercomponent interactions transiently used to promote the assembly typically do not 'live on' in the interlocked product, meaning that active template synthesis can be traceless and used for constructing mechanically interlocked molecules that do not feature strong binding interactions between the components. Since its introduction in 2006, active template synthesis has been used to prepare a variety of rotaxanes, catenanes and knots. Amongst the metal-ion-mediated versions of the strategy, the copper(I)-catalysed alkyne-azide cycloaddition (CuAAC) remains the most extensively used transformation, although a broad range of other catalytic reactions and transition metals also provide effective manifolds. In metal-free active template synthesis, the recent discovery of the acceleration of the reaction of primary amines with electrophiles through the cavity of crown ethers has proved effective for forming an array of rotaxanes without recognition elements, including compact rotaxane superbases, dissipatively assembled rotaxanes and molecular pumps. This Review details the active template concept, outlines its advantages and limitations for the synthesis of interlocked molecules, and charts the diverse set of reactions that have been used with this strategy to date. The application of active template synthesis in various domains is discussed, including molecular machinery, mechanical chirality, catalysis, molecular recognition and various aspects of materials science.
机械互锁分子结构的活性模板合成利用了各种结构元素（金属，或者在无金属活性模板合成的情况下，官能团的特定排列）的双重能力，使其既能作为构建模块组织的模板，又能作为促进它们之间形成共价键的催化剂。这使得缠绕或穿线的中间结构能够在动力学控制下被共价捕获。与传统的被动模板合成不同，用于促进组装的组分间相互作用通常不会在互锁产物中“保留”，这意味着活性模板合成可以无痕进行，并用于构建组分之间不存在强结合相互作用的机械互锁分子。自2006年被引入以来，活性模板合成已被用于制备各种轮烷、索烃和纽结。在该策略的金属离子介导版本中，铜（I）催化的炔烃-叠氮环加成反应（CuAAC）仍然是使用最广泛的转化反应，尽管其他多种催化反应和过渡金属也提供了有效的方法。在无金属活性模板合成中，最近发现通过冠醚腔加速伯胺与亲电试剂的反应对于形成一系列无识别元件的轮烷是有效的，包括紧凑型轮烷超强碱、耗散组装轮烷和分子泵。本综述详细介绍了活性模板概念，概述了其在合成互锁分子方面的优点和局限性，并梳理了迄今为止已用于该策略的各种反应。还讨论了活性模板合成在各个领域的应用，包括分子机器、机械手性、催化、分子识别以及材料科学的各个方面。
