Differences in adsorption among the components of complex mixtures play a role in separations, surface-based sensing, and heterogeneous catalysis, and have been implicated in theories of the origin of life. Herein, we consider mixtures of imines and we show that if such complex mixtures are also dynamic—that is, if their components equilibrate among themselves—then they can dramatically simplify in composition during the course of column chromatography. As they travel down the column, imines continuously trade their aldehyde and amine constituents, favoring the formation of molecules with extremes of polarity at the expense of species with intermediate polarities. Iterative application of this principle leads to simplification of imine libraries containing up to 16 members into 4 major products.

Two mesoporous fluorinated metal–organic frameworks (MOFs) were synthesized from extensively fluorinated tritopic carboxylate- and tetrazolate-based ligands. The tetrazolate-based framework MOFF-5 has an accessible surface area of 2445 m² g⁻¹, the highest among fluorinated MOFs. Crystals of MOFF-5 adsorb hydrocarbons, fluorocarbons, and chlorofluorocarbons (CFCs)—the latter two being ozone-depleting substances and potent greenhouse species—with weight capacities of up to 225 %. The material exhibits an apparent preference for the adsorption of non-spherical molecules, binding unusually low amounts of both tetrafluoromethane and sulfur hexafluoride.

Two mesoporous fluorinated metal–organic frameworks (MOFs) were synthesized from extensively fluorinated tritopic carboxylate- and tetrazolate-based ligands. The tetrazolate-based framework MOFF-5 has an accessible surface area of 2445 m² g⁻¹, the highest among fluorinated MOFs. Crystals of MOFF-5 adsorb hydrocarbons, fluorocarbons, and chlorofluorocarbons (CFCs)—the latter two being ozone-depleting substances and potent greenhouse species—with weight capacities of up to 225 %. The material exhibits an apparent preference for the adsorption of non-spherical molecules, binding unusually low amounts of both tetrafluoromethane and sulfur hexafluoride.

Differences in adsorption among the components of complex mixtures play a role in separations, surface-based sensing, and heterogeneous catalysis, and have been implicated in theories of the origin of life. Herein, we consider mixtures of imines and we show that if such complex mixtures are also dynamic—that is, if their components equilibrate among themselves—then they can dramatically simplify in composition during the course of column chromatography. As they travel down the column, imines continuously trade their aldehyde and amine constituents, favoring the formation of molecules with extremes of polarity at the expense of species with intermediate polarities. Iterative application of this principle leads to simplification of imine libraries containing up to 16 members into 4 major products.

We report structural characterization of a new member of m-phenylene ethynylene ring family. This shape-persistent macrocycle also co-crystallizes with hexafluoro-, 1,2,4,5-tetrafluoro-, 1,3,5-trifluoro, and 1,4-difluorobenzene. The four complexes are almost isostructural, and all show the fluoroarene included into the central cavity of the macrocycle. Characterized by multiple short CH⋅⋅⋅FC contacts, these inclusion complexes further dimerize in the solid state into a 2+2 assembly, in which the two macrocycles embrace each other by their large hydrophobic groups that are rotated by 60° relative to one another.

Cyanide-catalyzed benzoin condensation of terephthaldehyde produces a cyclic tetramer, which we propose to name cyclotetrabenzoin. Cyclotetrabenzoin is a square-shaped macrocycle ornamented with four α-hydroxyketone functionalities pointing away from the central cavity, the dimensions of which are 6.9×6.9 Å. In the solid state, these functional groups extensively hydrogen bond, resulting in a microporous three-dimensional organic framework with one-dimensional nanotube channels. This material exhibits permanent—albeit low-porosity, with a Langmuir surface area of 52 m² g⁻¹. Cyclotetrabenzoin’s easy and inexpensive synthesis and purification may inspire the creation of other shape-persistent macrocycles and porous molecular crystals by benzoin condensation.