Martínez-Aguirre Mayte A, Li Yan, Vanthuyne Nicolas, Bouteiller Laurent, Raynal Matthieu
Sorbonne Université, CNRS, Institut Parisien de Chimie Moléculaire, Equipe Chimie des Polymères, 4 Place Jussieu, 75005, Paris, France.
Aix Marseille Université, Centrale Marseille, CNRS, iSm2, UMR 7313, 13397, Marseille Cedex 20, France.
Angew Chem Int Ed Engl. 2021 Feb 19;60(8):4183-4191. doi: 10.1002/anie.202012457. Epub 2020 Dec 21.
Controlling the properties of supramolecular assemblies requires unveiling the specific interactions between their components. In the present work, the catalytic properties and structure of co-assemblies composed of a benzene-1,3,5-tricarboxamide (BTA) ligand coordinated to copper (the soldier) and seven enantiopure BTAs (the sergeants) have been determined. Whatever the sergeant, the enantioselectivity of the reaction is directly proportional to the optical purity of the supramolecular helices. More strikingly, the role played by the sergeant in the co-assembly process differs significantly: from almost pure intercalator (when it is incorporated in the stacks of the soldier and generates long homochiral helices) to pure chain capper (when it leads to the formation of partly helically biased and short assemblies). The former situation leads to optimal enantioselectivity for the catalytic system under study (58 % ee) while the latter situation leads to very low selectivity (8 % ee). The successful rationalization of this high and unexpected difference is crucial for the development of more efficient catalysts and more elaborate supramolecular systems.
控制超分子组装体的性质需要揭示其组分之间的特定相互作用。在本工作中，已确定了由与铜（“士兵”）配位的苯-1,3,5-三甲酰胺（BTA）配体和七个对映体纯的BTA（“中士”）组成的共组装体的催化性质和结构。无论“中士”是哪种，反应的对映选择性都与超分子螺旋的光学纯度成正比。更引人注目的是，“中士”在共组装过程中所起的作用有显著差异：从几乎纯粹的嵌入剂（当它并入“士兵”的堆叠中并产生长的同手性螺旋时）到纯粹的链封端剂（当它导致形成部分螺旋偏向且短的组装体时）。前一种情况导致所研究的催化体系具有最佳对映选择性（58% ee），而后一种情况导致非常低的选择性（8% ee）。成功合理解释这种高度且意外的差异对于开发更高效的催化剂和更精细的超分子体系至关重要。
