Search

Simple room-temperature self-assemblies between Cd2+ salts, SCN− and bisimidazole molecules at pH = 2 created three new organically templated thiocyanatocadmates [H2(L1)][Cd(SCN)4]·H2O (L1 = 1,4-bis(1H-imidazol-1-yl)benzene) 1, [H2(L2)][Cd(SCN)4] (L2 = 1,3-bis(2-methylimidazol-1-yl)propane) 2, and [H2(L3)][Cd2(SCN)6] (L3 = 1,4-bis(2-methyl-1H-imidazol-1-yl)butane) 3. X-ray single-crystal diffraction analysis reveals that (i) in 1–3, the SCN− groups doubly bridge the Cd2+ centers to form different thiocyanatocadmates: a linear chain in 1; a zigzag chain in 2; and a 2-D layer network (63 net) in 3; and (ii) in 1, via Nbase–H…NSCN interactions, the L1 molecules extend the thiocyanatocadmate chains into a 2-D supramolecular layer, whereas in 2, the zigzag thiocyanatocadmate chains self-assemble into a 3-D supramolecular network via weak S…S interactions. Photoluminescence analysis indicates that the three title compounds all emit light: blue light for 1 and 2 and green light for 3. At low temperatures, the emission positions of the three compounds hardly change, but the emission intensities are largely enhanced. Interestingly, after turning off the UV lamp, 1 and 2 still briefly emit light (ca. 2 s), which means that 1 and 2 possess phosphorescence properties. Phosphorescence lifetimes at 77 K are 1619 ms for 1 and 247 ms for 2. [ABSTRACT FROM AUTHOR]

Under hydro(solvo)thermal conditions, four organic bidentate bridging N,N′-donor ligands 1,3-bis(2-methylimidazol-1-yl)propane (L1), 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L2), 1,2-bis(2-methyl-1H-imidazol-1-ylmethyl)benzene (L3) and 5,6,7,8-tetrahydroquinoxaline (L4) were employed to react with CuBr/CuI, generating four 2-D layered copper(i)–polymer coordination polymer materials [Cu2Br2(L1)] 1, [CuI(L2)] 2, [CuI(L3)] 3 and [CuI(L4)0.5] 4. In 1–4, different Cu–X motifs are found: a cubic Cu4Br4 core in 1; a castellated Cu–I single chain in 2; a rhombic Cu2I2 core in 3; and a staircase-like Cu–I double chain in 4. The 2-D layer networks of 1–3 can all be simplified into a simple 44 topology (planar for 1 and 3; wave-like for 2), while the 2-D layer network of 4 has a 63 topology. The photoluminescence behaviors of 1–4 under a UV lamp suggest that 1 and 2 possess fluorescence thermochromism properties. Under the UV lamp, with the decrease in temperature, (i) 1 exhibits a yellow-to-red emission; (ii) 2 exhibits a yellow-to-green emission; (iii) 3 always emits green light; and (iv) 4 never emits light. These are further confirmed by their emission spectra. From 297 K to 77 K, the emission of 1 exhibits a large red shift from 561 nm to 623 nm; the emission of 2 exhibits a large blue shift from 571 nm to 515 nm; only a minor red shift is observed for the emission of 3; and no peaks appear in the emission spectra of 4. The crystal data of 1 and 2 at different temperatures have been collected for revealing the origination of their fluorescence thermochromism properties. Based on the above investigations, the effect of the rigidity/flexibility of the organic ligand on the fluorescence thermochromism properties of copper(i)–polymer coordination polymer materials is discussed. The quantum yields at 297 K and the photoluminescence lifetimes at 297 K and 77 K for 1–3 were also measured for better understanding their photoluminescence properties. [ABSTRACT FROM AUTHOR]

Abstract By employing the solvothermal in situ N -alkylation of organic bases with alcohol molecules, four new organically templated iodometallates as [L1][Ag 2 I 4 ] (L12+ = 1,1,4,4-tetramethyl-1λ4,4λ4-piperazinium) 1 , [L2] 1.5 [AgI 4 ] (L22+ = 1,4-dibenzyl-1λ4,4λ4-diazabicyclo[2.2.2]octanium) 2 , [L2] 1.5 [CuI 4 ] 3 and [L3][CuI 3 ] (L32+ = 4,4′-bis(3-methyl-1H-3λ4-imidazol-1-yl)-1,1′-biphenylium) 4 were obtained. In 1 , the in situ substitution and N-alkylation of 1,4-bis(pyridin-4-ylmethyl)piperazine (L1') with CH 3 OH has occurred, producing L12+. Templated by L12+, Ag+ and I- aggregate into a chained iodoargentate, which can be described as a linear arrangement of AgI 4 tedrahedra by sharing the edges. 2 and 3 are isostructural. In 2 and 3 , the in situ N -alkylation of 1,4-diazabicyclo[2,2,2]octane (L2') with phenylmethanol has occurred, generating L22+. Templated by L22+, Ag+ (or Cu+) and I- aggregate into a mononuclear iodometallate with a tetrahedral structure. In 4 , the in situ N -alkylation of 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl (L3') with CH 3 OH has occurred, creating L32+. Templating by L32+, Cu+ and I- aggregate into a mononuclear iodocuprate(I) with a planar trigonal structure. The photoluminescence analysis reveals that (i) at the room temperature, only 1 emits light (λ em = 550 nm); (ii) at the low temperature, 4 is found to possess the photoluminescence property (λ em = 546 nm at 77 K) with a ms-grade lifetime (τ = 4.915 ms). Graphical abstract By employing solvothermal in situ N -alkylation of organic bases with alcohol molecules, four new organically templated iodometallate(I) were obtained, and their photoluminescence properties were investigated. fx1 Highlights • Four new organically templated iodometallates(I) (M+ = Ag+, Cu+) are reported; • In situ N -alkylation of 1,4-diazabicyclo[2,2,2]octane with phenylmethanol is investigated for the first time; • In situ N -alkylation of 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl with alcohol molecules is investigated for the first time; • Their photoluminescence properties at different temperature are investigated. [ABSTRACT FROM AUTHOR]

The hydro(solvo)thermal reactions of CuI with diverse bisimidazole molecules were investigated, affording five new copper(I) iodides [Cu 4 I 4 (L1) 2 ] (L1=1,3-bis(2-methylimidazol-1-ylmethyl)benzene) 1 , [CuI(L2)] (L2=4,4′-bis(imidazolyl)biphenyl) 2 , [Cu 4 I 4 (L3)] (L3=1,3-bis(2-methylimidazol-1-yl)propane) 3 , [Cu 4 I 4 (L4) 2 ] (L4=1,4-bis(2-ethylimidazol-1-yl)butane) 4, and [Cu 4 I 4 (L5)] (L5=1,4-bis(1-imidazoly)benzene) 5 . X-ray single-crystal diffraction analysis reveals that (i) in 1 , a tetranuclear Cu-I cluster (stepped cubane) is observed, and the L1 molecule only acts as an ancillary ligand; (ii) in 2 , the L2 molecules extend the castellated Cu-I chains into a 2-D layer network with a certain thickness; (iii) in 2-D single-layer network of 3 , a 1-D Cu-I column is found, which can be viewed as a longitudinal packing of stepped Cu 4 I 4 cubanes; (vi) in 4 , the L4 molecules propagate the cubic Cu 4 I 4 cubanes into a 3-D 4-fold interpenetrated network with a cds topology; and (v) in 5 , the L5 molecules link the 1-D Cu-I ribbons into a 2-D single-layer network. The photoluminescence analysis indicates that 1 , 2 and 4 emit light (red light for 1 ; yellow light for 2 and 4 ), while 3 and 5 are not emissive. Their photoluminescence behaviors are confirmed to be related to the Cu···Cu interactions in the molecules. [ABSTRACT FROM AUTHOR]

Based on an aim of introducing the SCN − or SO 4 2 − group into the organically templated chlorocadmates, a series of room-temperature reactions at pH 2 were performed, creating four new Cd(II) hybrids as [L1] 4 [Cd 4 Cl 6 (SCN) 10 (H 2 O) 2 ] (L1 = 1,1′-dibenzyl-4,4′-bipyridium) 1 , [H 4 L2][CdCl 4 (SCN) 2 ] (L2 = 1,4-bis(4-pyridylmethyl)piperazine) 2 , [HL3] 3 [CdCl 3 ]SO 4 (L3 = 2-amino-6-chloropyridine) 3 , and [HL4] 3 [CdCl 3 ]SO 4 (L4 = 2-amino-6-bromopyridine) 4 . X-ray single-crystal diffraction analysis reveals that (i) templated by L1 2+ , 1 shows a 1-D single-chain structure, which is based on the dinuclear [Cd 2 Cl 3 (SCN) 4 (H 2 O)] 3 − clusters by the μ-1,3-mode SCN − groups; (ii) templated by H 4 L2 4+ , 2 only exhibits a mononuclear structure. However, via the intermolecular weak N pyridine H⋯Cl, N piperazine H⋯Cl and S SCN ⋯S SCN interactions, 2 self-assembles into a 3-D supramolecular network with a (4,6)-connected topology; (iii) 3 and 4 possess the similar structures. Via the N pyridine/amino H⋯O and π⋯π interactions, the introduced SO 4 2 − groups and the organic base molecules aggregate together into a 3-D supramolecular network with the 1-D channels. Within the channel, the Cl − ions triplely bridge the Cd 2+ centers into a 1-D linear [CdCl 3 ] − chain. Based on the structural information and the previous related reports, the role of the introduced SCN − or SO 4 2− group in the hybrid is revealed. SCN − acts as two roles: (i) a linker; (ii) a cutter. Sometimes SO 4 2− serves as a linker, while sometimes SO 4 2− connects with organic base into a supramolecular aggregation, acting as a new templating agent. The photoluminescence analysis reveals that 2 , 3 and 4 emit light with the maxima at 535 nm for 2 ( λ ex = 465 nm), 462 nm for 3 ( λ ex = 428 nm), and 465 nm for 4 ( λ ex = 430 nm), respectively. In particular, the emissions for all are strong, and can be seen under the ultraviolet (UV) lamp. [ABSTRACT FROM AUTHOR]