Synthesis,Structures, and Properties of a Series of New Coordination Polymers Built from 2‐Ethyl‐1H‐imidazole‐4,5‐dicarboxylate Ligand

A series of new coordination polymers, namely, [Sr(H₂EIDC)₂(H₂O)₂]_n ( 1 ),{[Pb(H₂EIDC)₂(H₂O)](H₂O)₃}_n ( 2 ), [Ag(H₂EIDC)]_n ( 3 ), and [Ba(H₂EIDC)₂(H₂O)]_n ( 4 ) (H₂EIDC = 2‐ethyl‐1H‐imidazole‐4,5‐dicarboxylate), were synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, X‐ray diffraction and thermogravimetric analyses. Complex 1 is a 2D infinite gridlike (4,4)topological layer structure. Complex 2 is a 2D corrugated layer constructed by Pb^II atoms and H₂EIDC^– anions. Complex 3 is a 2D corrugated sheet consisting of 1D chains linked by short Ag ··· Ag interactions, and the three complexes are extended into 3D supramolecular structures by weak intermolecular forces such as hydrogen bonds and π–π stacking interactions. Complex 4 exhibits a 3D framework with 1D channels. Furthermore, the luminescent properties of complexes 1 , 2 , and 3 are also investigated.     

Hydrothermal Synthesis,Crystal Structures and Effect of Non Bonding Interactions in Crystal Packing of Two Mixed‐Ligand Metal Complexes with Glycolato and 2,2′‐Dipiridylamine and with Benzilato and Imidazole

Two new mixed‐ligand complexes [Fe(HG)₂(dipyam)] ( 1 ) (HG = glycolato and dipyam = 2,2′‐dipyridylamine) and [Cu(HB)₂(im)₂]·2H₂O ( 2 ) (HB = benzilato and im = imidazole) have been hydrothermally synthesized and structurally characterised by X‐ray diffraction. In both cases the metallic centre is in an octahedral environment, strongly distorted in 2 (4+2 coordination). The α‐hydroxycarboxylato ligands (glycolato or benzilato) present different coordinative behaviour, bidentade chelate through the hydroxyl oxygen and one carboxy oxygen in 1 and through the two oxygen atoms of the carboxylate group in 2 . The complexes are extended into 2D frameworks through hydrogen bonding and π···π or C‐H···π interactions. The complexes were also characterized by elemental analysis, FT‐IR and UV‐vis spectroscopy and room temperature magnetic measurements.     

2D LnIII(Nd/La)‐AgI Heterometallic and TmIII Homometallic Coordination Polymers Based on Pyridine Dicarboxylate ­Ligands

Two 2D 4d‐4f heterometallic coordination polymers, [LnAg(Py26DC)₂(H₂O)₃] · 3H₂O [Ln = Nd ( 1 ), La ( 2 ); H₂Py26DC = pyridine‐2,6‐dicarboxylic acid], and one 2D lanthanide homometallic coordination polymer, [Ln(Py25DC)(ox)_0.5(H₂O)₂] [Ln = Tm ( 3 ); H₂Py25DC = pyridine‐2,5‐dicarboxylic acid; ox = oxalate], were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Both complexes 1 and 2 are isostructural and exhibit 3‐connected 2D heterometallic layer structures with the Schläfli symbol of (8² · 10), whereas complex 3 represents an extended 2D homometallic network structure with (4,4) topology.     

Three novel lanthanide complexes with imidazole-4,5-dicarboxylate ligand: Hydrothermal syntheses, structural characterization, and properties

Three novel lanthanide complexes, namely, [Ce(Himdc)(H₂imdc)(H₂O)₃]·H₂O (1), {[Dy(Himdc)(Ox)_0.5(H₂O)₂]·H₂O}_n (2), and {[Nd(Himdc)(Ox)_0.5(H₂O)₂]·H₂O}_n (3) (H₃imdc = imidazole-4,5-dicarboxylic acid, Ox = oxalate), have been successfully prepared by the assembly of lanthanide ions and H₃imdc ligand under different synthetic conditions. All of the complexes have been characterized by means of elemental analysis, IR, TG analysis, luminescence spectroscopy as well as single-crystal X-ray diffraction analysis. The 3D supramolecular structure of 1 is constructed from 1D zig-zag chains through the hydrogen bonding interactions. Complex 2 possesses the chair-shaped secondary building units (SBUs) with Dy₆(Himdc)₄(Ox)₂ and meso-helical chains (P + M), resulting in a novel 2D structure based on the linkages of oxalate ligand. Complex 3 also presents 2D layer structure with uninodal 6-connected net topology, but crystallizes in the different space group and owns higher coordination number of the central metal atom than complex 2. The luminescence property of 2 is investigated in the solid state at room temperature.     

Anthraquinone‐2,6‐disulfonate as Versatile Ligand for the Synthesis of Hydrogen‐Bonded Supramolecules

The reactions of anthraquinone‐2,6‐disulfonic acid disodium salt (Na₂a‐2,6‐dad) with Cu^II, Mn^II, and Zn^II with 1,10‐phenanthroline (phen) or 2,2′‐dipyridyl (bipy) under hydrothermal conditions formed two or three‐dimensional supramolecules of stoichiometries [Cu(a‐2,6‐dad)(phen)(H₂O)₃](H₂O)₄ ( 1 ), [Mn(a‐2,6‐dad)(bipy)₂(H₂O)](H₂O)₂ ( 2 ), and [Zn(a‐2,6‐dad)(bipy)₂(H₂O)](H₂O)₂ ( 3 ), which were synthesized and characterized. The arrangement around each metal atom is distorted octahedral. The ligands in all the compounds are engaged in intermolecular hydrogen bonding leading to the formation of hydrogen‐bonded networks, the compounds show novel π–π stacking interactions. Photoluminescence measurements indicate that the compound [Zn(a‐2,6‐dad)(bipy)₂(H₂O)](H₂O)₂ ( 3 ) shows strong blue luminescence in the solid state at room temperature.     

Synthesis,Crystal Structure and Characterization of a new Protonated Magnesium Borophosphate: (H3O)Mg(H2O)2[BP2O8]·H2O

A new protonated borophosphate (H₃O)Mg(H₂O)₂[BP₂O₈]·H₂O ( 1 ) was synthesized under mild hydrothermal conditions and characterized by single‐crystal X‐ray diffraction, FTIR spectroscopy and TG‐DTA. The compound crystallizes in the hexagonal system, space group P6(1)22 (No 178), a = 9.4462(7) Å, c = 15.759(2) Å, V = 1217.8(2) Å³, and Z = 6. There exist infinite helical $^1_\infty$ {[BP₂O₈]^3–} ribbons built up from corner‐sharing PO₄ and BO₄ tetrahedra, which are connected by MgO₄(H₂O)₂ leading to an infinite three‐dimensional open‐framework. The H₃O⁺ ions are located at the free thread of the helical ribbons, whereas crystallized water occupy the channels of the helical ribbons. The dehydration of the compound occurs at a higher temperature which is presumably due to the anisotropic hydrogen bonds in the crystal structure. The luminescent properties of the compound were studied.     

Mixed‐Ligand Complexes of Zinc(II) with α‐Hydroxycarboxylates and Aromatic N‐N Donor Ligands: Synthesis,Crystal Structures and Effect of Weak Interactions on their Crystal Packing

Several new two‐ligand complexes of zinc(II) with the aromatic N, N‐donor ligands 2, 2′‐bipyridine or 1, 10‐phenanthroline and one of three different α‐hydroxycarboxylates (HL′) derived of the α‐hydroxycarboxylic acids (H₂L′) (2‐methyllactic, H₂mL; mandelic, H₂M or benzilic, H₂B) were prepared. The compounds of formula [Zn(HL′)₂(NN)]·nH₂O (HL′ = HM, HB) were isolated as white powders and characterized by elemental analysis, IR spectroscopy and thermogravimetric analysis. The complexes of general formula [Zn(HL′)(NN)₂](HL′)·nH₂O (HL′ = HmL, HM) and [Zn(HB)₂(NN)₂], were obtained as single crystals and were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and X‐ray diffractometry. In all cases, the zinc atom is in a distorted octahedral environment. In [Zn(HL′)(NN)₂](HL′)·nH₂O the α‐hydroxycarboxylato ligands behave as bidentate chelating monoanion and an α‐hydroxycarboxylate as counterion is also present. In [Zn(HB)₂(NN)₂], the monoanionic benzilato ligand behaves as monodentate through one oxygen atom of the carboxylate function. The effect of the classical and no‐classical hydrogen bonding and of the π‐π and C‐H…π interactions in the 3D supramolecular arrangement of these molecular complexes is analyzed.     

Syntheses,Crystal Structures and Luminescent Properties of Three Inorganic‐Organic Hybrid Frameworks Constructed from 4,5‐Imidazoledicarboxylate

Three inorganic‐organic hybrid frameworks [Mn(HIMDC)(4,4′‐bipyo)_0.5(H₂O)]_n (1) , [Cd(H₂IMDC)₂(2,2′‐bipyo)] (2) and [Ca(HIMDC)(H₂O)₂·H₂O]_n (3) (H₃IMDC = 4,5‐imidazoledicarboxylate; 4,4′‐bipyo = 4,4′‐bipyridine‐N,N′‐dioxide; 2,2′‐bipyo= 2,2′‐bipyridine‐N,N′‐dioxide) have been hydrothermally synthesized and characterized by the elemental analyses, IR spectra, TG analysis and the single crystal diffraction. Both compounds 1 and 3 exhibit 2D layers while 2 is a monomer. It is noteworthy that compound 2 exhibits strong fluorescent emission in the solid state at room temperature.     

Hydrothermal Synthesis,Solid State Structure,and Thermal Properties of a Family of Isomorphous 1‐D Coordination Polymers Aggregated by Extensive Hydrogen Bonding: {[M(3,3′‐bpy)(H2O)4](SO4)·2H2O} (M = Co,Ni, Zn)

Hydrothermal synthesis has afforded a family of new coordination polymers incorporating 3,3′‐bipyridine (3,3′‐bpy), {[M(3,3′‐bpy)(H₂O)₄](SO₄)·2H₂O} (M = Co, Ni, Zn). The crystal structures revealed 1‐D undulating cationic ribbons of formulation {[M(3,3′‐bpy)(H₂O)₄]}_n²ⁿ⁺ with both unligated charge‐balancing sulfate anions and water molecules of crystallization entrapped by hydrogen bonding. The 1‐D ribbons run along the (101) crystal direction and further aggregate via extensive hydrogen bonding patterns. Thermal decomposition data were consistent with stepwise loss of water molecules of crystallization and aquo ligands followed by decomposition due to ligand removal.     

1‐Aminoindan‐2‐ol,a Suitable Ligand for the Synthesis of Chiral,Intramolecularly Stabilized Compounds of Aluminum,Gallium, and Indium

The reactions of enantiomerically pure (1R, 2S)‐(+)‐cis‐1‐aminoindan‐2‐ol, (1S, 2R)‐(‐)‐cis‐1‐aminoindan‐2‐ol, and racemic trans‐1‐aminoindan‐2‐ol with trimethylaluminum, ‐gallium, and ‐indium produce the intramolecularly stabilized, enantiomerically pure dimethylmetal‐1‐amino‐2‐indanolates (1R, 2S)‐(+)‐cis‐Me₂AlO‐2‐C*HC₇H₆‐1‐C*HNH₂ ( 1 ), (1S, 2R)‐(‐)‐cis‐Me₂AlO‐2C*HC₇H₆‐1‐C*HNH₂ ( 2 ), (1R, 2S)‐(+)‐cis‐Me₂GaO‐2‐C*HC₇H₆‐1‐C*HNH₂ ( 3 ), (1R, 2S)‐(+)‐cis‐Me₂InO‐2‐C*HC₇H₆‐1‐C*HNH₂ ( 4 ), (1S, 2R)‐(‐)‐cis‐Me₂InO‐2‐C*HC₇H₆‐1‐C*HNH₂ ( 5 ), and racemic (+/‐)‐trans‐Me₂InO‐2‐C*HC₇H₆‐1‐C*HNH₂ ( 6 ). The compounds were characterized by ¹H NMR, ¹³C NMR, ²⁷Al NMR and mass spectra as well as 1 and 3 to 6 by determination of their crystal and molecular structures. The dynamic dissociation/association behavior of the coordinative metal‐nitrogen bond was studied by low temperature ¹H NMR spectroscopy.     

Hydrothermal Syntheses,Crystal Structures,and Luminescent Properties of Three Organic‐Lanthanide Complexes with 3‐Hydroxycinnamic Acid

Three new homodinuclear lanthanide(III) complexes [Ln₂(L)₆(2,2′‐bipy)₂] [Ln = Tb^III ( 1 ), Sm^III ( 2 ), Eu^III ( 3 ); HL = 3‐hydroxycinnamic acid (3‐HCA); 2,2′‐bipy = 2,2′‐bipyridine] were synthesized and characterized by IR spectroscopy, elemental analyses, and X‐ray diffraction techniques. Complexes 1 – 3 crystallize in triclinic system, space group P$\bar{1}$ . In all complexes the lanthanide ions are nine‐coordinate by two nitrogen atoms from the 2,2′‐bipy ligand and seven oxygen atoms from one chelating L ligands and four bridging L ligands, forming distorted tricapped trigonal prismatic arrangements. The lanthanide(III) ions are intramolecularly bridged by eight carboxylate oxygen atoms forming dimeric complexes with Ln ··· Ln distances of 3.92747(15), 3.9664(6), and 3.9415(4) Å for complexes 1 – 3 , respectively. The luminescent properties in the solid state of HL ligand and Eu^III complex are also discussed.     

Synthesis,Structures, and Properties of Two Novel Supramolecular Architectures Constructed from [2,3‐f]Pyrazino[1,10]phenanthroline‐2,3‐dicarboxylic Acid

Two new compounds, [Ag(Hppdb)]_n ( 1 ) and {[Ag₂(Hppdb)₂(bpe)] · 5.5H₂O}_n( 2 ) [H₂ppdb = [2,3‐f]pyrazino[1,10]phenanthroline‐2,3‐dicarboxylic acid, bpe = trans‐1,2‐bis(4‐pyridyl)ethylene], were synthesized and characterized. In 1 , Hppdb^– ions link Ag^I cations to form an infinite 1D [–Ag–(Hppdb)–Ag–]_n chain, furthermore, the dimensionality is extended to 2D layers through synergistic π–π stacking, hydrogen‐bonding and weak Ag ··· O interactions. Correspondingly, the dimeric [(Ag)(Hppdb)]₂ subunits in 2 are connected by bpe ligands to generate a loop‐link‐shaped 1D chain motif, which is further joined through a R₂²(18)C–H ··· O hydrogen‐bonding ring to afford interesting diagonal/diagonal inclined catenation 2D + 2D → 3D supramolecular architectures. In addition, solid‐state properties such as photoluminescence and thermal stability of the two compounds were studied.     

Half‐Sandwich Iridium Complexes Bearing a Diprotic Glyoxime Ligand: Structural Diversity Induced by Reversible Deprotonation

Synthesis and deprotonation reactions of half‐sandwich iridium complexes bearing a vicinal dioxime ligand were studied. Treatment of [{Cp*IrCl(μ‐Cl)}₂] (Cp*=η⁵‐C₅Me₅) with dimethylglyoxime (LH₂) at an Ir:LH₂ ratio of 1:1 afforded the cationic dioxime iridium complex [Cp*IrCl(LH₂)]Cl ( 1 ). The chlorido complex 1 undergoes stepwise and reversible deprotonation with potassium carbonate to give the oxime–oximato complex [Cp*IrCl(LH)] ( 2 ) and the anionic dioximato(2?) complex K[Cp*IrCl(L)] ( 3 ) sequentially. Meanwhile, twofold deprotonation of the sulfato complex [Cp*Ir(SO₄)(LH₂)] ( 4 ) resulted in the formation of the oximato‐bridged dinuclear complex [{Cp*Ir(μ‐L)}₂] ( 5 ). X‐ray analyses disclosed their supramolecular structures with one‐dimensional infinite chain ( 1 and 2 ), hexagonal open channels ( 3 ), and a tetrameric rhomboid ( 4 ) featuring multiple intermolecular hydrogen bonds and electrostatic interactions.     

Four Dysprosium(III) Compounds Based On 1H‐Benzimidazole‐5,6‐dicarboxylic Acid via Hydrothermal Synthesis

Four compounds [Dy(H₂bidc)(Hbidc)(H₂O)₈] · 8H₂O ( 1 ), {[Dy(Hbidc)(H₂O)₂(Htzac)] · 3H₂O}_n ( 2 ), [Dy(C₂O₄)_0.5(Hbidc)(H₂O)₃]_n ( 3 ), {[Dy₂(Hbidc)₂(H₂O)(SO₄)] · H₂O}_n ( 4 ) (H₃bidc = 1H‐benzimidazole‐5,6‐dicarboxylic acid, H₂tzac = 1H‐3‐amino‐5‐carboxy‐1,2,4‐triazole) were synthesized with hydrothermal synthesis and structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. X‐ray analysis revealed that the four coordination compounds have different structures: Compound 1 is a three dimensional supermolecular structure joined by hydrogen bonding interactions based upon dinuclear units. Compound 2 is a three dimensional supermolecular structure combined by hydrogen‐bonding interactions based upon one dimensional coordination chain including a T4(1)‐type water cluster chain. The structure of compound 3 is built of two dimensional (3,6)‐connected kgd‐type (4³)₂(4⁶.6⁶.8³) layers with a right‐handed and a left‐handed helical chain, which are further extended into three dimensional supramolecular architecture by hydrogen bonding interactions. Compound 4 displays a three dimensional framework containing a dinuclear dysprosium building unit with a (3,8)‐connected (4.5²)₂(4².5¹⁰.6¹².7.8³) topological framework. In addition, the photoluminescent property of compound 3 was investigated.     

Monodentate Coordination of 4,4′‐Bipyridine Leading to a Supramolecular Network – Synthesis and Crystal Structure of [H2bpp][{Cu(Hbpy)2}{α‐HP2W18O62}]·4H2O

The new supramolecular compound [H₂bpp][{Cu(Hbpy)₂}{α‐HP₂W₁₈O₆₂}]·4H₂O ( 1 ) (bpy = 4,4′‐bipyridine, bpp = 1,3‐bis(4‐pyridyl)propane) was synthesized hydrothermally and characterized byelemental analysis, IR spectroscopy, thermogravimetric analysis and single‐crystal X‐ray diffraction. In compound 1 , the cationic fragment [Cu(Hbpy)₂]⁺ connects to the Dawson anion through a coordinating Cu←O bond, and the copper atom is coordinated by another polyoxoanion through a weak covalent bond with a Cu1–O26 distance of 2.879(2) Å, forming a polymeric chain. The bpy ligand in [Cu(Hbpy)₂]⁺ adopts a monodentate coordination mode, the other nitrogen atom of the bpy ligand is protonated. The protonated Hbpy⁺ acts as hydrogen‐bond donor and constructs a two‐dimensional double‐sheet supramolecular network involving the one‐dimensional chains through the hydrogen bonds. The H₂bpp²⁺ ion connects twoα‐HP₂W₁₈O₆₂^6– clusters from two supramolecular networks through hydrogen bonds and creates a three‐dimensional supramolecular architecture. The thermal decomposition of 1 happens over a wide temperature range (450–800 °C), which indicates that it might include complicated oxidation–reduction processes.     

A Self‐Assembled Calix[4]arene Dimer Linked through Hydrogen‐Bonded 2‐Ureidopyrimidin‐4(1H)‐one Groups

Tightly linked! A linear array of complementary hydrogen bonds forms between two 2‐ureidopyrimidin‐4(1H)‐one rings attached to the upper rims of facing 1,3‐alternate calix[4]arenes (shown schematically). The strength of the binding (K_ass>10⁶ M ⁻¹ in chloroform) and the efficiency of the self‐assembly open up interesting perspectives in the design of highly ordered multicomponent cages.     

Zur Hydrolyse von 2,3‐Dihydro‐1,3‐di‐tert‐butyl‐4,5‐dimethylimidazol‐2‐yliden. Die Kristallstruktur von 1,3‐Di‐tert‐butyl‐4,5‐dimethylimidazoliumhydrogencarbonat

On the Hydrolysis of 2,3‐Dihydro‐1,3‐di‐tert‐butyl‐4,5‐dimethylimidazol‐2‐ylidene. The Crystal Structure of 1,3‐Di‐tert‐butyl‐4,5‐dimethylimidazolium Bicarbonate 1,3‐Di‐tert‐butyl‐4,5‐dimethylimidazolium bicarbonate ( 7 ), formed on the exposure of 2,3‐dihydro‐1,3‐di‐tert‐butyl‐4,5‐dimethylimidazol‐2‐ylidene ( 6 ) towards air, is prepared on the reaction of 6 with ammonium bicarbonate; its crystal structure analysis reveals the presence of dimeric bicarbonate anions linked to each other and to the imidazolium ions with hydrogen bonds.     

2‐(2′‐Pyridyl)‐4,6‐diphenylphosphinine versus 2‐(2′‐Pyridyl)‐4,6‐diphenylpyridine: Synthesis,Characterization, and Reactivity of Cationic RhIII and IrIII Complexes Based on Aromatic Phosphorus Heterocycles

The bidentate P,N hybrid ligand 1 allows access for the first time to novel cationic phosphinine‐based Rh^III and Ir^III complexes, broadening significantly the scope of low‐coordinate aromatic phosphorus heterocycles for potential applications. The coordination chemistry of 1 towards Rh^III and Ir^III was investigated and compared with the analogous 2,2′‐bipyridine derivative, 2‐(2′‐pyridyl)‐4,6‐diphenylpyridine ( 2 ), which showed significant differences. The molecular structures of [RhCl(Cp*)( 1 )]Cl and [IrCl(Cp*)( 1 )]Cl (Cp*=pentamethylcyclopentadienyl) were determined by means of X‐ray diffraction and confirm the mononuclear nature of the λ³‐phosphinine–Rh^III and Ir^III complexes. In contrast, a different reactivity and coordination behavior was found for the nitrogen analogue 2 , especially towards Rh^III as a bimetallic ion pair [RhCl(Cp*)( 2 )]⁺[RhCl₃(Cp*)]^? is formed rather than a mononuclear coordination compound. [RhCl(Cp*)( 1 )]Cl and [IrCl(Cp*)( 1 )]Cl react with water regio‐ and diastereoselectively at the external P?C double bond, leading exclusively to the anti‐addition products [MCl(Cp*)( 1 H ? OH)]Cl as confirmed by X‐ray crystal‐structure determination.