Silva Hope A, Whitehead Bevan S, Hastings Christopher D, Tiwari Chandan Kumar, Brennessel William W, Barnett Brandon R
Department of Chemistry, University of Rochester, Rochester, New York 14627-0001, United States.
Organometallics. 2024 Sep 12;43(20):2599-2607. doi: 10.1021/acs.organomet.4c00247. eCollection 2024 Oct 28.
Porous organic cages (POCs) and metal-organic polyhedra (MOPs) function as zero-dimensional porous materials, able to mimic many functions of insoluble framework materials while offering processability advantages. A popular approach to access tailored metal-based motifs in extended network materials is postsynthetic metalation, which allows metal installation to be decoupled from framework assembly. Surprisingly, this approach has only sparingly been reported for molecular porous materials. In this report, we demonstrate postsynthetic metalation of tetrahedral [4 + 4] POCs assembled from tris(2-aminoethyl)amine (TREN) and 1,3,5-tris(4-formylphenyl)benzene. The trigonally symmetric TREN motif is a common chelator in coordination chemistry and, in the POCs explored herein, readily binds copper(I) and silver(I) to form cationic cages bearing discrete mononuclear coordination fragments. Metalation retains cage porosity, allowing us to compare the sorption properties of the parent organic and metalated cages. Interestingly, introduction of copper(I) facilitates activated oxygen chemisorption, demonstrating how targeted metalation can be exploited to tune the sorption characteristics of porous molecular materials.
多孔有机笼（POCs）和金属有机多面体（MOPs）作为零维多孔材料，能够模拟不溶性骨架材料的许多功能，同时具有可加工性优势。在扩展网络材料中获得定制金属基序的一种常用方法是后合成金属化，它使金属的引入与骨架组装脱钩。令人惊讶的是，这种方法在分子多孔材料中的报道很少。在本报告中，我们展示了由三（2-氨基乙基）胺（TREN）和1,3,5-三（4-甲酰基苯基）苯组装而成的四面体[4 + 4] POCs的后合成金属化。三角对称的TREN基序是配位化学中常见的螯合剂，在本文所研究的POCs中，它能很容易地与铜（I）和银（I）结合，形成带有离散单核配位片段的阳离子笼。金属化保留了笼的孔隙率，使我们能够比较母体有机笼和金属化笼的吸附性能。有趣的是，铜（I）的引入促进了活性氧的化学吸附，这表明如何利用有针对性的金属化来调节多孔分子材料的吸附特性。
