A facile solution-phase synthetic approach for constructing phenol-based porous organic cages and covalent organic frameworks

Abstract

A general solution-phase synthetic strategy is developed to construct both porous organic cages (POCs) and covalent organic frameworks (COFs) by simply stirring and heating organic solvent/water solutions of aldehydes and amines in the presence of MOH (M = Na, K, and Cs).

Reticular Chemistry in the Construction of Porous Organic Cages

“…The steep regions of the isotherm curves could be attributed to the micropore filling, while the more gentle regions might be due to the gas adsorption into larger pores created from interparticle voids. Their maximum N 2 adsorption capacities at P / P 0 = 0.99 and BET values are listed in Table , the latter of which are higher than most of the reported POCs (Figure d). − ,− Not all previously reported covalent organic cages provide gas sorption data, which demonstrate permanent porosity in the solid state; consequently, it is possible that some cages are, in fact, porous but their sorption isotherms have not been measured. The BET of CPOC-303 which is up to 2803 m 2 g –1 presents the highest in POCs synthesized by Schiff-base reactions, and only lower than the cuboctahedron [12 + 8] cage constructed from B–O bond formation reaction, which is very easily hydrolyzed and decomposes upon exposure to moisture, thus limiting its wider applications.…”

Conquering the crystallinity conundrum: efforts to increase quality of covalent organic frameworks

“…Base catalyzed imine COF formation was proven possible for four different materials. 186 However, it has to be noted that a phenol function on the aldehyde linker is necessary for this protocol. An aqueous solution of aldehyde and KOH was prepared to which the amine was added in organic solvent (N,N-diethylformamide, DEF or N,N-dimethylformamide, DMF).…”

Nanoscale covalent organic frameworks as theranostic platforms for oncotherapy: synthesis, functionalization, and applications

“…The hydrothermal synthesis of COFs is exceedingly rare, 93 while the preparation of COFs in a mixed solution of organic solvent and water has been realized. 94,95 For solvothermal synthesis, stainless steel reaction kettles with polytetrauoroethylene (PTFE) lining are the most general pressure vessels. Nevertheless, it is difficult to isolate the air, making it unsuitable for the synthesis of COFs.…”