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Abstract: Ruthenium‐containing organometallic ionic liquids with the B(CN)4 anion were developed that generate microporous amorphous coordination polymers upon UV irradiation. UV light irradiation of [Ru(C5H5)(C6H5R)][B(CN)4] (R=butyl, ethyl, octyl) quantitatively generated a yellow powder of a coordination polymer with the formula [Ru(C5H5){B(CN)4}]n. In this reaction, the arene ligand is eliminated by UV irradiation and coordination polymer is formed by coordination of the cyano groups of the anion to the Ru ion. The photogenerated solids exhibited nitrogen absorption properties due to their microporous structure. This paper proposes a method to fabricate functional coordination polymers by photoirradiation of liquids. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: coordination polymers; crystal structures; sandwich complexes; thermal properties; ionic liquids Coordination polymers, crystal structures, sandwich complexes, thermal properties, ionic liquids.

Although coordination polymers generally do not melt, several that do melt have been synthesized recently and have drawn much attention. In this study, two‐ and three‐dimensional coordination polymers that melt were synthesized, [Ru(Cp)(C6H5R)][M{C(CN)3}2] (R=H, Me, Et; M=K, Rb; Cp=C5H5), which are complex salts comprising M[C(CN)3] and organometallic ionic liquids [Ru(Cp)(C6H5R)][C(CN)3]. They have anionic [M{C(CN)3}2]n− coordination polymer frameworks, whose dimensionalities depend on the size of the organometallic cation inside. Their melting points decreased with increasing cation substituent length and size of the alkali metal ion (Tm=102–239 °C), and these low‐melting‐point coordination polymers exhibited incongruent melting, forming mixtures of solid M[C(CN)3] and ionic liquid upon melting. Using the same method, coordination polymers were synthesized with various bridging ligands, [Co(Cp)2][MX2] (X=B(CN)4, C(CN)3, N(CN)2; M=K, Na), as well as a paramagnetic coordination polymer, [Fe(Cp)2][K{C(CN)3}2]. [ABSTRACT FROM AUTHOR]

We present a new class of tunable aryl alkyl ionic liquids (TAAILs) containing different palladate counter ions. Solid‐state structures for representative compounds have been obtained. Their properties are presented in comparison to those of newly synthesized and reported palladate ionic liquids with conventional counter ions. It was found that the aryl substitution pattern and the type of anion have a profound influence on the melting point. The speciation of the different anions in solution has been rationalized by DFT calculations. Customize, adapt, overcome: Ionic liquids containing a palladate anion are accessible in a very flexible synthetic procedure. The choice of aryl substituent, alkyl group, type of palladate counter ion and halide ligand can all be modified to allow for fine‐tuning of the properties of a wide range of new compounds. [ABSTRACT FROM AUTHOR]

Abstract: The role of borate anions in ionothermal syntheses of crystalline chalcogenidometalates was shown by the directed ionothermal synthesis of seven new selenidostannates in ionic liquids with either [BF4]− or [B(CN)4]− anions. Single crystal structures are presented of four compounds, (C4C1C1Im)5[Sn9Se20][BF4] (1, Im=imidazolium), (DMMPH)4[Sn2Se6] (2, DMMP=2,6‐dimethylmorpholine), (C2C1Im)2(DMMPH)2[Sn6Se14] (3), and K2[Sn3Se7] (4), and how the chosen ionic liquid anion, and the reaction temperature, influences the product spectrum is discussed: Notably, 1 contains an entire formula unit of the ionic liquid, (C4C1C1Im)[BF4], while 4 contains neither the cation nor the anion of the ionic liquid—both observations being very uncommon for ionothermal syntheses. Three further compounds were obtained that exhibit strong disorder in the crystal structures (I‐III), for which only their anionic substructures are discussed herein. Compound 4 and I‐III are based on the same layered selenidostannate substructure, 2D‐{[Sn3Se7]2−}, yet with different inter‐layer distances, which is clearly reflected in the crystal colors and quantitative optical absorption properties. [ABSTRACT FROM AUTHOR]

The synthesis of anionic chalcogenidometalate superspheres can be achieved from [Ge4Se10]4− salts and SnCl4 in ionic liquids with 1-alkyl-(2,)3-(di)methylimidazolium cations, denoted as (C n(C1)C1Im)+ (alkyl = butyl for n=4, hexyl for n=6, octyl for n=8). Their formation is apparently independent from the lengths of the C n chain, and the presence or absence of a second methyl group at the ionic liquid cation (that are exchanged for alkali metal cations in precursor compounds during the reactions), although this may appear counterintuitive. In contrast, and equally counterintuitive, the ionic liquid anion was found to play a crucial role for both the general observability as well as the crystal yield and quality of the products, although they are not part of the product: a minimum content of chloride is needed, while ionic liquids with [BF4]− anions alone do not support the product formation/crystallization. The observation suggests a subtle equilibrium of SnCl4 with according halidostannate anions that decreases the reactivity of the tin source. The finding is of particular interest, as chloride anions were shown to have been major impurities of former 'chloride-free' ionic liquid charges, which potentially led to irreproducible synthesis protocols in the literature. [ABSTRACT FROM AUTHOR]