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We present the first ambient mechanosynthesis of 16 flexible covalent organic frameworks (COFs) within an hour. Notably, one representative COF exhibited a high iodine uptake capacity of ∼4.3 g g⁻¹from aqueous solutions and 5.97 g g⁻¹from vapor. 

Abstract The rapid and environmentally benign synthesis of metal‐immobilized covalent organic frameworks (metal/COFs) for heterogeneous catalysis is a pervasive challenge, as the mainstream synthesis is exceedingly time‐consuming (up to four days) and demands the use of hazardous solvents. Herein, we describe a sustainable and efficient one‐step sonochemical strategy for constructing diverse palladium (II)‐immobilized COFs (Pd(II)/COFs). By merging the sonochemistry‐assisted COF synthesis and in situ Pd (II) immobilization into a single step, this strategy enables the rapid formation of Pd(II)/COF hybrids within an hour under ambient conditions using water as the solvent. Notably, gram‐scale synthesis of Pd(II)/COFs is achievable. The resulting Pd(II)/COFs exhibit superb crystallinity and high surface area, leading to remarkable activity, excellent functionality tolerance, and high recyclability for the Suzuki–Miyaura cross‐coupling reaction of aryl bromides and arylboronic acids at room temperature. This one‐step sonochemical strategy effectively addresses the long‐lasting limitations of traditional multistep synthesis, paving a fast and sustainable avenue to diversified metal/COF hybrids for heterogeneous catalysis and potentially other applications. 

Abstract Tuning the topology of two‐dimensional (2D) covalent organic frameworks (COFs) is of paramount scientific interest but remains largely unexplored. Herein, we present a site‐selective synthetic strategy that enables the tuning of 2D COF topology by simply adjusting the molar ratio of an amine‐functionalized dihydrazide monomer (NH₂−Ah) and 4,4′,4′′‐(1,3,5‐triazine‐2,4,6‐triyl)tribenzaldehyde (Tz). This approach resulted in the formation of two distinct COFs: a clover‐like 2D COF with free amine groups (NH₂−Ah−Tz) and a honeycomb‐like COF without amine groups (Ah−Tz). Both COFs exhibited good crystallinity and moderate porosity. Remarkably, the clover‐shaped NH₂−Ah−Tz COF, with abundant free amine groups, displayed significantly enhanced adsorption capacities toward crystal violet (CV, 261 mg/g) and congo red (CR, 1560 mg/g) compared to the non‐functionalized honeycomb‐like Ah−Tz COF (123 mg/g for CV and 1340 mg/g for CR), underscoring the pivotal role of free amine functional groups in enhancing adsorption capacities for organic dyes. This work highlights that the site‐selective synthetic strategy paves a new avenue for manipulating 2D COF topology by adjusting the monomer feeding ratio, thereby modulating their adsorption performances toward organic dyes.