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Abstract The exploitation of noncovalent bonding in the solid state is attractive to generate one‐dimensional (1D) wire‐like assemblies of metals and uncover dynamic and physical properties of such intriguing structures. Herein, we describe a metal‐organic crystal based on Ag(I) ions that assemble to be organized into 1D wire‐like assemblies maintained by argentophilic interactions. UV‐light irradiation of the crystal composed of the 1D structures results in a single‐crystal‐to‐single‐crystal (SCSC) photodimerization that transforms the 1D periodic metal arrays to isolated metal dimers. The structural reconfiguration creates small voids in the crystal and the resulting solids exhibit a substantial increase in softness up to 60%. 

Abstract A method to rapidly diversify the molecules formed in organic crystals is introduced, with aryl nitriles playing a novel dual role as both hydrogen‐bond acceptors and modifiable organic groups. The discovery of coexisting supramolecular synthons in the same crystal is also described. The general concept is demonstrated by using a bis(aryl nitrile) alkene that undergoes a hydrogen‐bond‐directed intermolecular [2+2] photodimerization to form a tetra(aryl nitrile)cyclobutane. The product is readily converted by click reactivity to a tetra(aryl tetrazole) and by hydrolysis to a tetra(aryl carboxylic acid). The integration of aryl nitriles into solid‐state reactions opens broad avenues to post‐modify products formed in crystalline solids for rapid diversification. 

Abstract Cocrystallizations of diboronic acids [1,3‐benzenediboronic acid (1,3‐bdba), 1,4‐benzenediboronic acid (1,4‐bdba) and 4,4’‐biphenyldiboronic acid (4,4’‐bphdba)] and bipyridines [1,2‐bis(4‐pyridyl)ethylene (bpe) and 1,2‐bis(4‐pyridyl)ethane (bpeta)] generated the hydrogen‐bonded 1 : 2 cocrystals [(1,4‐bdba)(bpe)₂] (1), [(1,4‐bdba)(bpeta)₂] (2), [(1,3‐bdba)(bpe)₂(H₂O)₂] (3) and [(1,3‐bdba)(bpeta)₂(H₂O)] (4), wherein 1,3‐bdba involved hydrated assemblies. The linear extended 4,4’‐bphdba exhibited the formation of 1 : 1 cocrystals [(4,4'‐bphdba)(bpe)] (5) and [(4,4'‐bphdba‐me)(bpeta)] (6). For 6, a hemiester was generated by an in‐situ linker transformation. Single‐crystal X‐ray diffraction revealed all structures to be sustained by B(O)−H⋅⋅⋅N, B(O)−H⋅⋅⋅O, O_w−H⋅⋅⋅O, O_w−H⋅⋅⋅N, C−H⋅⋅⋅O, C−H⋅⋅⋅N, π⋅⋅⋅π, and C−H⋅⋅⋅π interactions. The cocrystals comprise 1D, 2D, and 3D hydrogen‐bonded frameworks with components that display reactivities upon cocrystal formation and within the solids. In 1 and 3, the C=C bonds of the bpe molecules undergo a [2+2] photodimerization. UV radiation of each compound resulted in quantitative conversion of bpe into cyclobutane tpcb. The reactivity involving 1 occurred via 1D‐to‐2D single‐crystal‐to‐single‐crystal (SCSC) transformation. Our work supports the feasibility of the diboronic acids as formidable structural and reactivity building blocks for cocrystal construction.