In a decade, many porous coordination polymers have been synthesized, providing a variety of properties ranging from storage, separation, exchange of guests in their cavities, magnetism, conductivity and catalysis by their frameworks. In this tutorial review, we focus on the hydrogen bonding type arrangements for dynamic porous coordination polymers exhibiting elastic guest accommodations, in contrast to rigid three-dimensional (3-D) frameworks. Such dynamic porous properties induce highly-selective guest accommodation and magnetic modulation, and could now be considered a new class of practical materials.

Dynamic porous properties of coordination polymers inspired by hydrogen bonds

A low-temperature, solution-based preparation of amorphous, metal oxide semiconducting thin-films is reported. This ‘sol–gel on chip’ hydrolysis approach yields thin-film transistors with high field-effect mobilities, reproducible and stable turn-on voltages and high operational stability.

Low-temperature, high-performance solution-processed metal oxide thin-film transistors formed by a ‘sol–gel on chip’ process

A well-known organic host compound undergoes single-crystal-to-single-crystal phase transitions upon guest uptake and release. Despite a lack of porosity of the material, guest transport through the solid occurs readily until a thermodynamically stable structure is achieved. In order to actively facilitate this dynamic process, the host molecules undergo significant positional and/or orientational rearrangement. This transformation of the host lattice is triggered by weak van der Waals interactions between the molecular components. In order for the material to maintain its macroscopic integrity, extensive cooperativity must exist between the molecules throughout the crystal, such that rearrangement can occur in a well-orchestrated fashion. We demonstrate here that even weak dispersive forces can exert a profound influence over solid-state dynamics.

https://science.sciencemag.org/content/sci/298/5595/1000.full.pdf

Guest transport in a nonporous organic solid via dynamic van der Waals cooperativity

Exploitation of the hydrogen bond: recent developments in the context of crystal engineering

Zerovalent palladium and nickel complexes of heterocyclic carbenes: Oxidative addition of organic halides, carbon-carbon coupling processes, and the Heck reaction

CHOLIC acid forms multimolecular inclusion compounds with a variety of organic substances1. Some of these inclusion compounds have crystal structures containing channels2, which can perform efficient chiral recognition of, for example, lactones3; others, with ethanol4 or water5 as guest molecules for example, have no such channels. Although these two types of structure seem at first to be very different, we report here results that indicate that they are closely related. In particular we present the novel finding that guests can be added, removed or exchanged without the intervention of an amorphous state. We suggest that cholic acid crystals have a dynamic layered structure which can be modified to incorporate guests by rearrangement of the intermolecular hydrogen-bonded networks. To our knowledge, this is the first example of intercalation in organic crystals accompanied by guest-responsive on-off control of channels, although many similar inorganic intercalation compounds (of graphite and clay, for example) are known6,7. These observations suggest that small molecules can express significant molecular information when assembled into crystalline structures.

Kunio Miki

Papers

Guest-responsive structural changes in cholic acid intercalation crystals

A simplest isolable monocyclic thiepin. Synthesis, structure, and thermal stability of 2,7-di-tert-butylthiepin

The molecular structure of chlorothiomethoxymethyltriphenylphosphinepalladium(II) at −160 and 20°C

The preparation and X-ray molecular structure of a novel dialkylpalladium(II) compound containing bridged thiophenoxymethyl groups

A Novel Aromatic Hydrocarbon with 16π‐Electron Periphery: “Cyclic Bicalicene”