The synthesis of multi-walled nanostructures represents a formidable challenge owing to the limitations imposed by existing synthetic strategies. Herein, we report a strategy involving molecular-strain engineering (MSE) for constructing double-walled polyhedra from strained bow-shaped macrocycles called molecular bows (MBs). As a proof of concept, four double-walled tetrahedra have been assembled from L-shaped dual-panels subtending ∼70.5° and producing MBs, which incorporate porphyrin and o-xylylene units, forming strained shape-persistent conformations. The head-to-tail closed-loop stacking of these units, driven by complementary non-covalent bonding interactions, leads to a large porphyrin-lined tetrahedron encapsulating a small o-xylylene-lined tetrahedron. The synergistic aromatic shielding effects emanating from the porphyrin tetrahedron result in the largest upfield chemical shifts of −7.7 ppm for protons and −8.8 ppm for carbons from those for the free dual panels. This demonstration, which features the launching of MSE for constructing sophisticated supramolecular nanostructures, could herald a fresh approach to the fabrication of multi-porphyrin photocatalytic systems.

由于现有合成策略的限制，多壁纳米结构的合成是一项艰巨的挑战。在此，我们报告了一种涉及分子应变工程 (MSE) 的策略，用于从称为分子弓 (MB) 的应变弓形大环构建双壁多面体。作为概念的证明，四个双壁四面体由 L 形双面板组装而成，对着 ~70.5°并产生 MB，其中包含卟啉和邻二甲苯单元，形成应变形状持久构象。这些单元的头对尾闭环堆叠，由互补的非共价键相互作用驱动，导致大的卟啉内衬四面体封装一个小的o-二甲苯衬里的四面体。卟啉四面体产生的协同芳香屏蔽效应导致质子的最大高场化学位移为 -7.7 ppm，碳为 -8.8 ppm，来自自由双面板。该演示的特点是启动 MSE 以构建复杂的超分子纳米结构，可能预示着一种制造多卟啉光催化系统的新方法。