Organometallic Ionic Plastic Crystals Incorporating Cationic Half-Sandwich Complexes.

Ionic plastic crystals (IPCs), characterized by nearly spherical molecular ions, exhibit remarkable solid-state characteristics including high ionic conductivity. However, most IPCs are organic onium salts. Incorporating organometallic half-sandwich complexes into IPCs is challenging owing to their low-symmetry structures.

Controlling Ionic Conductivity in Organometallic Ionic Liquids through Light-Induced Coordination Polymer Formation and Thermal Reversion.

Owing to their high ionic conductivity and negligible vapor pressure, ionic liquids (ILs) find applications in various electronic devices. However, fabricating IL-based photocontrollable devices remains a challenge. In this study, we developed organometallic ILs with reversible light- and heat-controlled ionic conductivities for potential use in tunable devices.

Solvent-free transformation of protic ionic liquids into zwitterions.

We synthesized several protic ionic liquids (ILs) composed of onium cations and the (trifluoromethylsulfonyl)(vinylsulfonyl)amide anion. The addition of a base catalytically facilitated their transformation into zwitterions (ZIs) under solvent-free conditions, which is a convenient method for synthesizing ZIs from ILs.

Incongruent Melting and Vitrification Behaviors of Anionic Coordination Polymers Incorporating Ionic Liquid Cations.

Several meltable coordination polymers (CPs) that possess substantial advantages attributable to their high flexibility and processability have been developed recently; however, the melting mechanism and vitrification conditions of these materials are not yet fully understood. In this study, we synthesized meltable CPs [A][K(TCM)] (A = onium cation, TCM = C(CN)) incorporating ionic liquid components and investigated their crystal structures and melting behaviors in detail. These CPs feature two- or three-dimensional anionic [K(TCM)] frameworks incorporating onium cations.

On-demand gelation of ionic liquids using photoresponsive organometallic gelators.

The reversible formation of ionic liquid gels, or ionogels, upon external stimuli could improve their versatility and expand their application scope in electronic, biomedical, and micro-engineering systems. Herein, we developed organometallic compounds that release low-molecular-weight gelators upon photoirradiation, which facilitate the on-demand photogelation of ionic liquids (ILs). The chemical formulae of the gelator-coordinated complexes are [Ru(CH)L]X (L = CHNHCONHCH; X = PF, B(CN)).

Photoinduced and Thermal Linkage Isomerizations of an Organometallic Ionic Liquid Containing a Half-Sandwich Ruthenium Thiocyanate Complex.

Metal complexes with thiocyanate (SCN) ligands typically exhibit - or -coordinated linkage isomers. In this study, to explore ionic liquids that exhibit stimuli-responsiveness based on linkage isomerization, we synthesized an ionic liquid containing a cationic half-sandwich thiocyanate complex, [Ru(CH)(NCS)L]TfN (L = -hexyl-2-pyridinemethanimine, TfN = bis(trifluoromethanesulfonyl)amide anion). The as-synthesized ionic liquid was a 0.

Thermal properties, crystal structures, and phase diagrams of ionic plastic crystals and ionic liquids containing a chiral cationic sandwich complex.

To investigate the effects of chirality on the phase behavior of ionic plastic crystals and ionic liquids, salts of a chiral sandwich complex with various anions were synthesized. The synthesized salts have the general chemical formula [Ru(C5H5)(C6H5CHCH3OCH3)]X (X = CB11H12, CF3BF3, PF6, CPFSA (= [double bond, length as m-dash]CF2(SO2CF2)2N)), where the ruthenium complex possesses a chiral substituent. The racemates of the salts with the CB11H12, CF3BF3, and PF6 anions crystallized as a solid solution, racemic compound, and conglomerate, respectively.

Reversible formation of soft coordination polymers from liquid mixtures of photoreactive organometallic ionic liquid and bridging molecules.

The reversible switching of bonding modes in coordination polymers through the application of external stimuli leads to versatile mechanical and electronic functions. However, the exploration of such a system remains a great challenge. In this study, we designed liquid mixtures comprising a photoreactive organometallic ionic liquid and a bridging ligand, which form intermolecular coordination bonds upon photoirradiation.

Reversible control of ionic conductivity and viscoelasticity of organometallic ionic liquids by application of light and heat.

Ru-containing ionic liquids [Ru(CH){CH(OCHCN)}][N(SOF)] (1) and [Ru(CH){CH(OCHCN)}][N(SOF)] (2), having different numbers of substituents, were reversibly converted to coordination polymer solids and oligomeric liquids, respectively, by UV photoirradiation and heating. This feature enabled the control of their ionic conductivities and viscoelastic properties.

Synthesis and Reactivity of Cyclopentadienyl Ruthenium(II) Complexes with Tris(alkylthio)benzenes: Transformation between Dinuclear and Sandwich-Type Complexes.

To explore the structural transformation of cyclopentadienyl ruthenium (CpRu) complexes in response to external stimuli, the reaction of [RuCp(MeCN)][X] (X = PF, (FSO)N [= FSA]) and tris(alkylthio)benzenes (1,3,5-CH(SR); : R = Pr, : R = Me) was investigated, and the crystal structures and thermal properties of the products were examined. The reaction produced the sandwich complexes [RuCp ][X] or dinuclear complexes [RuCp(μ- )(CHCN) ][X] (X = PF, FSA) depending on the reaction conditions. The sandwich complex [RuCp ][FSA] was an ionic liquid.