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Covalent organic frameworks (COFs), a burgeoning class of crystalline porous materials constructed by covalently connecting organic building blocks, have garnered tremendous attention. The predominant solvothermal synthesis of COFs usually requires high temperature and long reaction times (three days or longer), which creates substantial obstacles for their accelerated discovery and exploration in practical applications. Hence, the expeditious synthesis of COFs without compromising their inherent properties is exceedingly appealing from the viewpoint of cost, time, and energy footprint. To overcome the sluggishness of the synthesis, considerable efforts have been invested in the rapid synthesis of high-quality COFs through innovations in energy source, catalyst, solvent, monomer, nucleation, and workup activation, leading to a drastic reduction of reaction time from multiple days to a few hours, and even to seconds in some cases. In this contribution, we provide a comprehensive overview of the advances in expediting the synthesis science of COFs. Though a nascent effort, six prevalent strategies have been identified for the rapid synthesis of COFs, which have led to intriguing applications in a diverse range of areas including gas adsorption, separation, heterogeneous catalysis, environmental remediation, and photodynamic therapy. We also outline the major challenges and perspectives on the future directions empowered by expeditious COF synthesis.

Magnetic multi-enzyme nanosystems have been prepared via co-precipitation of enzymes and metal–organic framework HKUST-1 precursors in the presence of magnetic Fe3O4 nanoparticles. The spatial co-localization of two enzymes was achieved using a layer-by-layer positional assembly strategy. Glucose oxidase (GOx) and horseradish peroxidase (HRP) were used as the model enzymes for cascade biocatalysis. By controlling the spatial positions of enzymes, three bienzyme nanosystems GOx@HRP@HKUST-1@Fe3O4, GOx–HRP@HKUST-1@Fe3O4 and HRP@GOx@HKUST-1@Fe3O4 were prepared in which GOx and HRP containing layers were in close proximity, either encapsulated in the HKUST-1 inner layer, or immobilized on the HKUST-1 outer shell, or randomly distributed in the two MOF layers. Their properties were characterized by transmission electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermal gravimetric analysis, and zeta potential measurements. The highest activity was observed at pH = 6 and a temperature of 20 °C. Thanks to the favorable positioning of enzymes, the GOx@HRP@HKUST-1@Fe3O4 nanosystem revealed superior kinetics with a Michaelis constant Km = 0.8 mmol L−1 and the maximum reaction rate Vmax = 11.3 μmol L−1 min−1. The enzyme–HKUST-1 conjugates exhibited remarkably high operational stability compared to the free enzymes. This work provides a facile and versatile approach to spatially organized multienzyme systems with well-defined nanostructures and greatly enhanced the overall biocatalytic efficiency.

pH-responsive surface layers consisting of porous polymer monoliths containing thiol groups have been prepared via a "thiol-ene" click reaction using a mixture of hydrophobic and ionizable unsaturated "ene" compounds. A proportion of these two "ene" reagents controlled the wettability of the surface that varied with pH, and enabled reversible switching between superhydrophilic and superhydrophobic properties.

The preparation of porous polymer monoliths with dodecyl and zwitterionic functionalities via the “thiol-ene” click chemistry of thiol-containing monoliths with both hydrophobic and polar methacrylate “ene” monomers has been demonstrated. Selected separations confirmed the excellent potential of these monoliths in chromatography.