Alkoxo-bridged copperII complexes as nodes in designing solid-state architectures. The interplay of coordinative and d10-d10 metal-metal interactions in sustaining supramolecular solid-state architectures

Four novel polymeric coordination networks have been obtained through self-assembly processes involving alkoxo-bridged copperII species as nodes, and anionic cyano-complexes as linkers: infinity2[{Cu2(pa)2}{M(CN)2}2](M=Ag, 1; Au, 2), (infinity)3[{Cu4(mea)4}{Au(CN)2}4.H2O]3, and (infinity)3[{Cu2(pa)2}{Ni(CN)4}](pa = deprotonated propanolamine; mea = deprotonated monoethanolamine). The supramolecular architectures of compounds 1, and 2 are sustained by argentophilic or strong aurophilic interactions. The solid-state architectures of 1 and 2, which are isomorphous, consist of infinite layers, constructed from binuclear alkoxo-bridged nodes and [M(CN)2]- spacers. The layers are stacked in an offset parallel mode, and are further interconnected through Ag...Ag or Au...Au contacts (1: Ag...Ag 3.015 A; 2: Au....Au 3.069 A). Compound 3 consists of unique fourfold interpenetrating diamondoid nets. The diamondoid topology is built of heterocubane {Cu4O4} nodes, which are connected by [Au(CN)2]- rods. The Cu-O distances within the {Cu4O4} node vary between 1.927(2) and 2.679(1) A, showing unsymmetric bridging of the copper atoms. Aurophilic interactions are established between the bridging and terminal [Au(CN)2]- metalloligands, and connect the interpenetrating nets, resulting in infinite chains of gold atoms (the Au...Au distances vary between 3.253 and 3.305 [Angstrom]). Compound 4 exhibits a 3-D network constructed from {Cu2(pa)2]2+ nodes connected by square-planar [Ni(CN)4]2- ions. Compounds 1, 2 and 4 are weakly paramagnetic. The cryomagnetic investigation of reveals a gradual increase, followed by a decrease of the chiMT product, as the temperature is lowered. A superposition of ferro- (J1=+20.8 cm(-1)) and antiferromagnetic (J2=-6.4) interactions within the tetranuclear node was found. Antiferromagnetic interactions are established between the tetranuclear nodes (theta=-2.99 K).     

Solid-State Decarboxylation of Cyclophane Tetra(malonatemethylene) Derivative

Russian Journal of General Chemistry - Heat-induced solid-state decarboxylation of tetra(malonatemethylene) based cyclophane leads to its tetra(2-carboxyethyl) derivative in quantitative yield....     

Synthesis of four new carboxylic derivatives based on the [1.1.1.1]metacyclophane backbone blocked in 1,3-Alternate conformation

Four new tetrasubstituted [1.1.1.1]metacyclophanes (4–7), that are inherently adopting a 1,3-Alternate conformation, bearing four or eight peripheral carboxylic binding sites, and appended with spacers group (alkyl or phenyl) differing by the flexibility, have been synthesised in high yields. The structures of the obtained compounds have been investigated in solution as well as in the solid state, for three of them, by using single-crystal X-ray analysis.     

Molecular tectonics: design and generation of charge-assisted, H-bonded, hybrid molecular networks based on amidinium cations and thio- or isothio-cyanatometallates

Upon combining the bis-amidinium dication 1-2H(+) with thiocyanatometallate M(SCN)(4)(2-) (M = Pd, Hg) or isothiocyanatometallate Cu(NCS)(4)(2-) anions (behaving as H-bond donor and acceptors, respectively) three new hybrid molecular networks have been obtained in the crystalline phase and structurally characterized by X-ray diffraction on single crystals. Whereas for the combination of tecton 1-2H(+) and both Pd(SCN)(4)(2-) and Hg(SCN)(4)(2-) anions analogous 1-D H-bonded networks were observed, for the Cu(NCS)(4)(2-) anion a 2-D network was obtained. Based on structural features of both components, the formation of the two types of networks is discussed.     

Light-induced metastable states in oxalatenitrosylruthenium(II) and terpyridinenitrosylruthenium(II) complexes

Two extremely long lived metastable states (SI and SII) can be accessed by irradiation with light in the blue-green spectral range at temperatures below 200 K in Cs(2)[Ru(ox)(NO)Cl(3)], [Ni(cyclam)][Ru(ox)(NO)Cl(3)].3H(2)O, and [Ru(terpy)(NO)(OH)Cl][PF(6)]. The crystal structures of the ground states of the oxalate-containing compounds are presented, and the influence of the atomic distances of the cations/anions is discussed with respect to the decay temperatures. The radiationless thermal decay of the metastable states is detected by differential scanning calorimetry (DSC) for the three compounds. Both metastable states decay exponentially in time under isothermal conditions. The excited states are energetically separated from the ground state by potential barriers given by the activation energy of the Arrhenius law. In [Ni(cyclam)][Ru(ox)(NO)Cl(3)].3H(2)O the enthalpy maximum of the thermal decay of SII appears at 182 K, which is a relatively high decay temperature for SII. The reason for this strong temperature shift compared to those of the other compounds could be due to the polarization effect of Ni(2+) on the electron density at the Ru site via the Cl atom.     

From tectons to luminescent supramolecular ionic liquid crystals

New phosphorescent and room-temperature liquid-crystalline materials were obtained by combining dicyanometallate anions with dicationic bisamidinium based tectons bearing four peripheral lipophilic pyrogallate moieties.     

Molecular tectonics: silver coordination networks based on tetramercaptothiacalix[4]arene in 1,3-alternate conformation bearing four nitrile groups

Russian Chemical Bulletin - Two tetrasubsituted derivatives of tetramercaptothiacalix[4]arene in 1,3-alternate conformation bearing either four (3-cyano)propyl (1) or (4-cyano)benzyl (2) moieties...