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Designed porosity in coordination materials often relies on highly ordered crystalline networks, which provide stability upon solvent removal. However, the requirement for crystallinity often impedes control of higher degrees of morphological versatility, or materials processing. Herein, we describe a supramolecular approach to the synthesis of amorphous polymer materials with controlled microporosity. The strategy entails the use of robust metal–organic polyhedra (MOPs) as porous monomers in the supramolecular polymerization reaction. Detailed analysis of the reaction mechanism of the MOPs with imidazole-based linkers revealed the polymerization to consist of three separate stages: nucleation, elongation, and cross-linking. By controlling the self-assembly pathways, we successfully tuned the resulting macroscopic form of the polymers, from spherical colloidal particles to colloidal gels with hierarchical porosity. The resulting materials display distinct microporous properties arising from the internal cavity of the MOPs. This synthetic approach could lead to the fabrication of soft, flexible materials with permanent porosity.

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A diarylethene having two nitronyl nitroxides, 1,2-bis[6-(1-oxyl-3-oxide-4,4,5,5-tetramethylimidazolin-2-yl)-2-methyl-1-benzothiophen-3-yl]hexafluorocyclopentene (2a), was synthesized in an attempt to control the intramolecular magnetic interaction by photoirradiation. The photochemical conversions from open-ring isomer 2a to closed-ring isomer 2b and from 2b to 2a were both almost 100%. Magnetic measurement revealed the antiferromagnetic interaction between two nitronyl nitroxides remarkably increased from 2J/k B = −2.2 K to 2J/k B = −11.6 K when the diarylethene spin coupler was switched from the open-ring isomer 2a to the closed-ring isomer 2b. ESR measurements were also carried out for both 2a and 2b in benzene solutions at room temperature and in MTHF solid solutions at cryogenic temperature. Both ESR and magnetic measurement indicated that the intramolecular interaction was switched by the photochromic spin coupler.

Efficient trans-hydroarylation of alkynes by simple arenes has been realized regio-and stereoselectively at room temperature in the presence of Pd(II) or Pt(II) catalysts and a mixed solvent containing trifluoroacetic acid (TFA). Various arenes undergo trans-hydroarylation selectively across terminal and internal C-C triple bondssincluding those conjugated to CHO, COMe, CO 2 H, and CO 2 Et groups, affording kinetically controlled cis-arylalkenes predominantly in most cases, especially, in good yields for electron-rich arenes and activated alkynes. The formation of arene/alkyne 1/2 or 2/1 adducts as side products is dependent on the arenes' and alkynes' substituents, which can be suppressed in some cases by changing the catalyst, catalyst concentration, and reaction time. The Pt(II) system, PtCl 2 /2AgOAc/TFA, shows lower catalytic activity than Pd(OAc) 2 /TFA, but higher selectivity, giving higher yields of adducts at the same conversion. On the basis of several isotope experiments and control reactions, a possible mechanism involving electrophilic metalation of aromatic C-H bonds by in-situ-generated cationic Pd(II) and Pt(II) species leading to intermolecular transarylpalladation to alkynes has been discussed.