Tuning water adsorption, stability, and phase in Fe-MIL-101 and Fe-MIL-88 analogs with amide functionalization.

Metal-organic frameworks (MOFs) of the MIL series of materials have been widely studied as a result of their high tunability and the diversity of structure types that exist for these typically M containing frameworks. We explored the use of amide-functionalized ligands in the synthesis of Fe-MIL-101 as a means to tune the water stability and water vapor adsorption in this important class of frameworks. We further show that slow leaching of Fe from NdFeB magnets can afford MIL-101 or MIL-88 under various conditions where the phase of the framework is controlled by length of the carbon chains on amide substituents.

Design and synthesis of aryl-functionalized carbazole-based porous coordination cages.

A subset of coordination cages have garnered considerable recent attention for their potential permanent porosity in the solid state. Herein, we report a series of functionalized carbazole-based cages of the structure type M(R-cdc) (M = Cr, Cu, Mo) where the functional groups include a range of aromatic substituents. Single-crystal X-ray structure determinations reveal a variety of intercage interactions in these materials, largely governed by pi-pi stacking.

Synthesis and characterization of low-nuclearity lantern-type porous coordination cages.

Permanent porosity in lantern-type ML paddlewheel-based cages is rare and has only been reported for naphthalene, naphthyridine, and diethynylbenzene-based linkers. This work presents the design, synthesis, and characterization of small lanterns that exhibit CO accessible BET surface areas in excess of 200 m g. The crystal packing and porosity of these cages can be tuned by either ligand functionalization or the choice of M source used in their synthesis.

Tuning the Porosity, Solubility, and Gas-Storage Properties of Cuboctahedral Coordination Cages via Amide or Ester Functionalization.

The molecular nature of porous coordination cages can endow these materials with significant advantages as compared to extended network solids. Chiefly among these is their solubility in volatile solvents, which can be leveraged in the synthesis, characterization, modification, and utilization of these adsorbents. Although cuboctahedral, paddlewheel-based coordination cages have shown some of the highest surface areas for coordination cages, they often have limited solubility.

A Charged Coordination Cage-Based Porous Salt.

Metal-organic frameworks and porous coordination cages have shown incredible promise as a result of their high tunability. However, syntheses pursuing precisely targeted mixed functionalities, such as multiple ligand types or mixed-metal compositions are often serendipitous, require postsynthetic modification strategies, or are based on complex ligand design. Herein, we present a new method for the controlled synthesis of mixed functionality metal-organic materials via the preparation of porous salts.

Atomically Precise Crystalline Materials Based on Kinetically Inert Metal Ions via Reticular Mechanopolymerization.

Atomistic control of the coordination environment of lattice ions and the distribution of metal sites within crystalline mixed-metal coordination polymers remain significant synthetic challenges. Herein is reported the mechanochemical synthesis of a reticular family of crystalline heterobimetallic metal-organic frameworks (MOFs) is now achieved by polymerization of molecular Ru [II,III] complexes, featuring unprotected carboxylic acid substituents, with Cu(OAc) . The resulting crystalline heterobimetallic MOFs are solid solutions of Ru and Cu sites housed within [M L ] phases.

Elucidating the Structure of the Metal-Organic Framework Ru-HKUST-1.

Ru-HKUST-1 (; ) has received considerable attention as a result of its structure type, tunability, and the redox-active nature of its constituent metal paddlewheel building units. As compared to some of the other members of the HKUST-1 family, its surface area is typically reported as ~25% lower than expected. In contrast to this, a related ruthenium-based porous coordination cage, , displays the expected surface area when compared to and analogs.

Design and synthesis of capped-paddlewheel-based porous coordination cages.

To leverage the structural diversity of metal-organic frameworks, the ability to controllably terminate them for the isolation of porous coordination cages is advantageous. However, the strategy has largely been limited to ligand termination methods, particularly for paddlewheel-based materials. Here, we show a paddlewheel-capping strategy can be employed to afford previously unattainable coordination cage structures that are mimetic of metal-organic framework pores.

Understanding Gas Storage in Cuboctahedral Porous Coordination Cages.

Porous molecular solids are promising materials for gas storage and gas separation applications. However, given the relative dearth of structural information concerning these materials, additional studies are vital for further understanding their properties and developing design parameters for their optimization. Here, we examine a series of isostructural cuboctahedral, paddlewheel-based coordination cages, M(Bu-bdc) (M = Cr, Mo, Ru; Bu-bdc = 5--butylisophthalate), for high-pressure methane storage.

Methane Storage in Paddlewheel-Based Porous Coordination Cages.

Although gas adsorption properties of extended three-dimensional metal-organic materials have been widely studied, they remain relatively unexplored in porous molecular systems. This is particularly the case for porous coordination cages for which surface areas are typically not reported. Herein, we report the synthesis, characterization, activation, and gas adsorption properties of a family of carbazole-based cages.

Gas adsorption in an isostructural series of pillared coordination cages.

The synthesis and characterization of two novel pillared coordination cages is reported. By utilizing 1,4-diazabicyclo[2.2.