Polycatenated 2D Hydrogen-Bonded Binary Supramolecular Organic Frameworks (SOFs) with Enhanced Gas Adsorption and Selectivity.

Controlled assembly of two-dimensional (2D) supramolecular organic frameworks (SOFs) has been demonstrated through a binary strategy in which 1,4-bis-(4-(3,5-dicyano-2,6-dipyridyl)pyridyl)naphthalene (), generated by oxidative dehydrogenation of 1,4-bis-(4-(3,5-dicyano-2,6-dipyridyl)dihydropyridyl)naphthalene (), is coupled in a 1:1 ratio with terphenyl-3,3',4,4'-tetracarboxylic acid (; to form ), 5,5'-(anthracene-9,10-diyl)diisophthalic acid (; to form ), or 5,5'-bis-(azanediyl)-oxalyl-diisophthalic acid (; to form ). Complementary O-H···N hydrogen bonds assemble 2D 6- (honeycomb) subunits that pack as layers in to give a three-dimensional (3D) supramolecular network with parallel channels hosting guest DMF (DMF = ,'-dimethylformamide) molecules. and feature supramolecular networks of 2D → 3D inclined polycatenation of similar layers as those in . Although suffers framework collapse upon guest removal, the polycatenated frameworks of and exhibit excellent chemical and thermal stability, solvent/moisture durability, and permanent porosity. Moreover, their corresponding desolvated (activated) samples and display enhanced adsorption and selectivity for CO over N and CH. The structures of these activated compounds are well described by quantum chemistry calculations, which have allowed us to determine their mechanical properties, as well as identify their soft deformation modes and a large number of low-energy vibration modes. These results not only demonstrate an effective synthetic platform for porous organic molecular materials stabilized solely by primary hydrogen bonds but also suggest a viable means to build robust SOF materials with enhanced gas uptake capacity and selectivity.