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The clathrate-I borosilicide K8−xBySi46−y (0.8 ≤ x ≤ 1.2 and 6.4 ≤ y ≤ 7.2; space group Pmn) was prepared in sealed tantalum ampoules between 900 °C and 1000 °C. By high-pressure preparation at 8 GPa and 1000 °C, a higher boron content is achieved (x = 0.2, y = 7.8). Crystal structure and composition were established from X-ray diffraction data, chemical analysis, WDX spectroscopy, and confirmed by 11B and 29Si NMR, and magnetic susceptibility measurements. The compositions are electron-balanced according to the Zintl rule within one estimated standard deviation. The lattice parameter varies with composition from a = 9.905 A for K7.85(2)B7.8(1)Si38.2(1) to a = 9.968(1) A for K6.80(2)B6.4(5)Si39.6(5).

The clathrate-I borosilicide K

Isonicotine amide, picoline amide, pyrazine 2-amide, 2- and 4-amino benzamides and various CuII salts were used to target CuII complexes of these ligands alongside with 1D and 2D coordination polymers. Under the criterion of obtaining crystalline and single phased materials a number of new compounds were reliably reproduced. Remarkably, for some of these compounds the ideal Cu:ligand ratio of the starting materials turned out to be very different from Cu:ligand ratio in the products. Crystal and molecular structures from single-crystal XRD were obtained for all new compounds, phase purity was checked using powder XRD. We observed exclusively the Oamide and not the NH2amide function binding to CuII. In most of the cases, this occurred in chelates with the second pyridine, pyrazine or aminophenyl N function. &micro, O,N ditopic bridging was frequently observed for the N = pyridine, pyrazine or aminophenyl functions, but not exclusively. The geometry around CuII in these compounds was very often axially elongated octahedral or square pyramidal. X-band EPR spectra of powder samples revealed various spectral symmetry patterns ranging from axial over rhombic to inverse axial. Although the EPR spectra cannot be unequivocally correlated to the observed geometry of CuII in the solid state structures, the EPR patterns can help to support assumed structures as shown for the compound [Cu(Ina)2Br2] (Ina = isonicotine amide). As UV-vis absorption spectroscopy and magnetic measurement in the solid can also be roughly correlated to the surrounding of CuII, we suggest the combination of EPR, UV-vis spectroscopy and magnetic measurements to elucidate possible structures of CuII compounds with such ligands.

The reaction between tridentate NNO donor hydrazone ligands, (E)-2-cyano-N′-(phenyl(pyridin-2-yl)methylene)acetohydrazide (HL1) and (E)-2-cyano-N′-(1-(pyridin-2-yl)ethylidene)acetohydrazide (HL2), with MnCl2·4H2O in methanol resulted in [Mn(HL1)Cl2(CH3OH)] (1) and [Mn(HL2)Cl2(CH3OH)] (2). Molecular structures of the complexes were determined by single-crystal X-ray diffraction. All of the investigated compounds were further characterized by elemental analysis, FT-IR, TGA, and UV–Vis spectroscopy. These complexes were used as catalysts for olefin oxidation in the presence of tert-butylhydroperoxide (TBHP) as an oxidant. Under similar experimental conditions with equal manganese loading, the presence of [Mn(HL2)Cl2(CH3OH)] (2) resulted in higher conversion than [Mn(HL1)Cl2(CH3OH)] (1).

Reaction of various sulphur ligands L (SEt−, SPh−, SC6F4H-4−, SEt2, StBu2, SnBu2, DMSO, DPSO) with the precursors [(COD)M(R)Cl] (COD = 1,5-cyclooctadiene, M = Pd or Pt; R = methyl (Me) or benzyl (Bn); DMSO = dimethyl sulfoxide; DPSO = diphenyl sulfoxide) allowed isolation and characterisation of mononuclear neutral (n = 0) or cationic (n = 1) complexes [(COD)Pt(R)(L)]n+. Reaction of l -cysteine (HCys) with [(COD)Pt(Me)Cl] under similar conditions gave the binuclear cationic complex in [{(COD)Pt(Me)}2(μ-Cys)]Cl. Detailed NMR spectroscopy and single crystal X-ray diffraction in the case of [(COD)Pt(Me)(SEt2)][SbF6] and [(COD)Pt(Me)(DMSO)][SbF6] reveal markedly labilised Pt–S bonds as a consequence of the highly covalent Pt–C bonds of the R coligands in these organometallic species. Cationic charge (n = 1) seems to lower the Pt–S bond strength further. Consequently, most of these complexes are not stable long-term in aqueous DMF (N,N-dimethylformamide) solutions. This made the evaluation of their antiproliferative properties towards HT-29 colon carcinoma and MCF-7 breast adenocarcinoma cell lines impossible. Only the two complexes [(COD)Pt(R)(SC6F4H-4)] with R = Me or SC6F4H-4 coligands could be tested with the R = Me complex showing promising activity (in the range of cisplatin), while the R = SC6F4H-4 derivative is largely inactive, as were the phosphane complexes [(dppe)Pt(SC6F4H-4)2] (dppe = 1,2-bis(diphenylphosphino)ethane), cis-[(PPh3)2Pt(SC6F4H-4)2] and cis-[(PPh3)2PtCl2] which were tested for comparison. In turn, our findings might pave the way to new Pt anti-cancer drugs with largely reduced unwanted depletion of incorporated drugs and reduced side-effects from binding to S-containing biomolecules.

Synthesis and structural characterization of six monomeric, heteroleptic tantalum(V) complexes of the general formula Ta(OiPr)4(ArTFP), where Ar = pyridine (1), 4,5- dimethyloxazole (2), 4,5-dimethylthiazole (3), benzimidazole (4), benzoxazole (5), benzthiazole (6), and TFP = trifluoropropenol, are described. Introduction of a donor-functionalized β-heteroarylalkenolate in the coordination sphere of Ta in the dimeric Ta2(OiPr)10 increases significantly the stability and volatility of these precursors, simplifying the depositions of Ta2O5. The molecular structures of 1–6 exhibited a distorted octahedral coordination around the tantalum center by four isopropoxide groups and one β-heteroarylalkenolate. Thermal decomposition studies (TG/DTA) and analysis of byproducts by NMR spectroscopy confirmed the decomposition mechanism and gas-phase stability of the heteroleptic compounds necessary for Ta2O5 depositions. Chemical vapor deposition studies with 1 and 2 demonstrated their suitability as efficient precurso...

The synthesis, spectroscopy, structures and chemical reactivity of platinum(II) diolefin complexes cis-[(∥∧∥)PtCl2], cis-[(∥∧∥)PtCl(R)] and cis-[(∥∧∥)Pt(R)2] [∥∧∥ = chelate diolefin ligand: 1,5-cyclooctadiene (COD), 1,5-dimethylocta-1,5-diene (Me2COD), norbornadiene (NBD), 1,5-hexadiene (HEX), 3-allyloxypropene (All2O, diallyl ether), diallylamine (All2NH); R = Me, Bn, C6F5, C6F4H-4 (or -5), or C≡C(4-Me)Ph] have been explored. The relative exchange rates of the cis-[(∥∧∥)PtCl2] complexes towards the diimine ligand diisopropyl-1,4-diazabutadiene (iPr-DAB) increased along the series COD < Me2COD < NBD < HEX < All2O by a factor of 4. The presumably dimeric complex [(All2NH)PtCl2]2 undergoes a unique rearrangement process in dimethyl sulfoxide (DMSO) solution to yield the dimeric piperazine complex [PtCl(dmso)(C6H10N)]2, which has been characterised by single-crystal XRD. For selected platinum complexes, cytotoxic effects in HT-29 colon carcinoma and MCF-7 breast cancer cell lines were evaluated. For comparison, the dicationic complexes [(COD)Pt(Bn)(L)][PF6]2 with the very labile coligands N-methyl-4,4′-bipyridinium (MQ+) and N-methyl-1,4-pyrazinium (Mpz+) were added to the study. Although the hexadiene complexes [(HEX)Pt(C6F4H-4)2] and [(HEX)Pt(C6F4H-5)2] show strong cytotoxicity, the introduction of labile diolefin ligands or the labile cationic MQ+ or Mpz+ coligands does not generally lead to markedly increased cytotoxicity.

The reaction of HSC6F4H-4 and base with suitable platinum(II) chlorido precursor complexes leads to mononuclear complexes containing diimine ligands [(N^N)Pt(SC6F4H-4)2], or [(N^N)Pt(Me)(SC6F4H-4)] (N^N = 2,2′-bipyridine (bpy), dipyrido[3,2-a:2′,3′-c]phenazine (dppz) or 11-trifluoromethyl-dipyrido[3,2-a:2′,3′-c]phenazine (CF3dppz)), cycloocta-1,5-diene (COD) complexes [(COD)Pt(SC6F4H-4)2] or [(COD)Pt(R)(SC6F4H-4)] (R = Me, Bn (benzyl) or C6F5), or phosphine complexes cis-[(PPh3)2Pt(SC6F4H-4)2], [(dppe)Pt(SC6F4H-4)2] (dppe = 1,2-bis(diphenylphosphino)ethane) and [(dppb)Pt(C6F5)(SC6F4H-4)] (dppb = 1,4-bis(diphenylphosphino)butane). Reaction of cis-[(DMSO)2PtCl2] lead to the labile cis- and trans-[(DMSO)2Pt(SC6F4H-4)2] which rapidly lose DMSO to yield polymeric [Pt(SC6F4H-4)2]m. Reaction of HSC6F4H-4 and KOtBu with K2PtCl4 gave K2[Pt(SC6F4H-4)4]. The new compounds were analysed and characterised by single crystal XRD, 1H, 19F and 195Pt NMR and IR spectroscopy. Both single crystal XRD (in the solid) and NMR (in solution) reveal that the ligand strength of the thiolate ligand −SC6F4H-4 strongly depends on the further ligands in the complexes. The crystal structures exhibit various inter- and intra molecular π stacking interactions of the SC6F4H-4 coligands. The absorption spectroscopy and electrochemistry of the diimine complexes [(N^N)Pt(SC6F4H-4)2] (N^N = bpy, dppz and CF3dppz) have been investigated and reveal that the Pt complexes are superior to the recently reported Pd derivatives in view of their application in photoactive materials.

Attempted syntheses of AgRf·DMAP were performed using the established route starting from AgF and Me3SiRf (Rf = CF3, C2F5, C6F5) followed by the addition of DMAP. Unexpectedly, reactions with perfluoroalkylsilver(I) derivatives yielded products, which underwent known equilibria, while exclusively the pentafluorophenyl derivative exhibits its zwitterionic nature in solution and in the solid state. Moreover, both perfluoroalkyl derivatives investigated decomposed slowly but more or less selectively even at –20 °C in solution: AgC2F5·DMAP mainly into AgOCOCF3 (probably under the influence of moisture) and AgCF3·DMAP mainly into the unprecedented derivative 3-trifluoromethyl-4-dimethylaminopyridine. The molecular structure of AgC6F5·DMAP was elucidated showing a twist arrangement of the aromatic rings quite unusual for linear coordinated species.

The first rare-earth metal telluride chlorides, RTeCl with R = La, Ce, Pr, Nd, were obtained as single crystals and/or powder samples by the reaction of anhydrous rare-earth trichlorides, RCl3, with the respective rare-earth metals R and elemental tellurium (Te) in sealed tantalum containers at temperatures as high as 1050 °C. All four telluride-chlorides crystallize with the so-called tetragonal PbFCl type of structure but according to RTeCl = PbClF, with, for the example of LaTeCl-I, a = 451.7(1), c = 827.4(2) pm, VE/Z = 84.5(1) A3, tetragonal, P4/nnm (No. 129). LaTeCl and CeTeCl are dimorphic, the second modification crystallizes with the PbCl2 type of structure with, for LaTeCl-II, a = 795.2(1), b = 450.8(1), c = 940.4(1) pm, VE/Z = 84.3(1) A3, orthorhombic, Pnma (No. 62). In both structures, La3+ is nine-coordinate, [LaTe5Cl4], with similar mean La–Te and La–Cl distances in both modifications, 333.2 vs. 333.1 pm and 302.9 vs. 301.8 pm, respectively.

The reaction of HSC6F4H-4 or KSC6F4H-4 with the palladium(II) complexes [(NN)PdCl2] [NN = 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen)] leads to the mononuclear palladium complexes [(NN)Pd(SC6F4H-4)2] or [(NN)PdCl(SC6F4H-4)], whereas the reaction with [(COD)PdCl2] (COD = 1,5-cyclooctadiene) results in the loss of COD and the formation of the oligonuclear species [Pd(SC6F4H-4)2]m. For NN = phen, the compound [(phen)2K(μ-phen)2K(phen)2][(4-HC6F4S)2Pd(μ-SC6F4H-4)2Pd(SC6F4H-4)2] containing a homoleptic dimeric dianionic Pd complex was also obtained. The reaction of KSC6F4H-4 with PdCl2 yielded K2[Pd(SC6F4H-4)4]. The new compounds were analysed and characterised by single-crystal XRD, 1H and 19F NMR spectroscopy and IR spectroscopy. The UV/Vis absorption spectroscopy and electrochemistry of [(bpy)Pd(SC6F4H-4)2] have been investigated and are compared to those of the related Pt derivative [(bpy)Pt(SC6F5)2].

Conditions for the addition of trialkyl(trifluorovinyl)silanes to the carbonyl- and thiocarbonyl function of commercially available isocyanates and isothiocyanates in the presence of tetramethylammonium fluoride (TMAF) to give corresponding amides of 2,3,3-trifluoroacrylic and 2,3,3-trifluorothioacrylic acids have been elaborated. The behaviour of the synthesized amides towards fluoride ions was studied. The syntheses of the amides of 2,3,3,3-tetrafluoropropionic and 2,3,3,3-tetrafluorothiopropionic acids and some unexpected cyclic products with the β-lactam structure are described. The molecular structures of the c -hexyl amide of 2,3,3,3-tetrafluoropropionic acid and two isomers of β-lactams deriving from the reaction of the tert -butyl amide of 2,3,3-trifluoroacrylic acid with a fluoride source have been elucidated by XRD measurements.

The new three-dimensional coordination polymer {[Bi(NNO)2(NO3)]·1.5H2O}n(1, NNO−= nicotinateN-oxide) was synthesized and characterized by elemental analysis, IR and1H-NMR spectroscopy, as well as single-crystal X-ray diffraction analysis.1crystallizes in the monoclinic space group C2/c. The crystal structure consists of a rectangular-shaped grid constructed with NNO linkers. Cavities of a diameter of 7.9–8.3 Å2are filled with disordered water molecules. The thermal stability of the compound was evaluated by thermogravimetric analysis.

Reaction of various sulphur ligands L (SEt

The new intermetallic compound Ru 11 Lu 20 was obtained as black single crystals during an attempted comproportionation reaction of lutetium(III) chloride, LuCl 3, with metallic lutetium in the presence of ruthenium metal at 950 °C. Ru 11 Lu 20 crystallizes with the trigonal space group R-3, Z = 6, a = 1255.1(1), c = 2973.0(4) pm, R1 for all data: 0.0380. Ruthenium atoms center eight-, nine- and ten-vertex polyhedra of lutetium atoms which are connected in a complicated manner to a three-dimensional network.

Three new mixed-ligand complexes of silver(I) with 4,4ʹ-bipyridine and derivates of benzoyltrifluoroacetone (Htfpb: 4,4,4-trifluoro-1-phenyl-1,3-butandione, Htfcpb: 4,4,4-trifluoro-1-(4- chlorophenyl)-1,3-butandione and Htfmpb: 4,4,4-trifluoro-1-(4-methoxyphenyl)-1,3-butandione) were synthesized and characterized by elemental analyses and 1H NMR spectroscopy. Thermal and electrochemical properties were also studied. The single-crystal structure of [Ag(4,4ʹ-bpy)(tfcpb)]n shows a one-dimensional coordination polymer as a result of 4,4ʹ-bpy bridging. The four-coordinate Ag(I) ions are linked into double chains by Ag...O contacts, which are extended into a 3D supramolecular structure through abundant weak interactions, such as μ...μ, C-H...F, C-H...O, C-H...Cl and F...F contacts.

Se(C5F4N)2 and Te(C5F4N)2 were prepared via redox transmetalations of AgC5F4N and the corresponding elements in good yields. The crystal structures of both derivatives exhibit infinite chains caused by a weak intermolecular contact between the chalcogen and one nitrogen atom with a T-shaped (ψ-pentagonal-bipyramidal) ligand arrangement. Crystallization of both reagents from dimethylsulfoxide gave single crystals of the corresponding 1:1 adducts that crystallize in infinite chains best expressed by the formula [E(C5F4N)2·(μ-DMSO)]∞ (E = Se, Te). In these cases, the coordination spheres of selenium and tellurium are square-planar (ψ-octahedral). Similar effects are found in the molecular structures of [Te(C5F4N)2·TMTU]∞ and [Te(C6F5)2·TMTU]∞ (TMTU = tetramethylthiourea). Differences in the Te–S interatomic distances clearly indicate the C5F4N ligand being significantly more electron-withdrawing in comparison with the C6F5 group; that is, Te(C5F4N)2 is the stronger Lewis acid.

MeTeRf (Rf = CF3, C2F5) can easily be prepared via the reactions of methyl iodide and the corresponding tetramethylammonium perfluoroalkyltellurates(0), [NMe4]TeRf (Rf = CF3, C2F5). Both compounds are easily oxidized by xenon difluoride and the heavier halogens to yield the corresponding dihalides, MeTe(Rf)X2 (X = F, Cl, Br, I) and by ArI(OCOCF3)2 to give the corresponding trifluoroacetates, MeTe(Rf)(OCOCF3)2. All compounds are characterized byspectroscopic means. The molecular structures of MeTe(Rf)F2,MeTe(Rf)Cl2, MeTe(Rf)Br2, and of 4-MeC6H4I(OCOCF3)2 were elucidated by XRD methods.

The crown-ethers 12-crown-4 (12c4) and benzo-12-crown-4 (b12c4) encapsulate divalent manganese, iron, cobalt, and nickel cations building large sandwich-type dications with square-antiprismatic coordination polyhedra; benzo-15-crown-5 (b15c5) forms in-cavity complexes with six-plus-one coordinate Mn(II) and Co(II). The anions are a variety of polyiodides, I3–, I5–, I7–, I122–, I162–, and I184–. The crystal structures of 12 new compounds have been determined, 8 of which contain 12-crown-4: [Mn(12c4)2](I3)2(12c4) (1) and [Co(12c4)2](I3)2(12c4) (2) are isotypic (monoclinic, C2/c, No. 15) and contain isolated triiodide anions. Isotypic [Mn(12c4)2](I5)2 (3) and [Ni(12c4)2](I5)2 (4) (monoclinic, Cm, No. 8) feature V/L-shaped I5– anions which are connected to zigzag chains. The hexadecaiodides, built of nonaiodide and heptaiodide subunits, in the isotypic compounds [Mn(12c4)2](I16) (5), [Fe(12c4)2](I16) (6), [Co(12c4)2](I16) (7) (orthorhombic, Pna21, No. 33) exhibit a new structural motif for I162– anions. The e...

A reaction of YI3, dibenzo-24-crown-8 and iodine in ethanol yielded, as a by-product, red single crystals of (I2)@(db24c8). In the triclinic crystal, P-1, a = 485.0(1), b = 1203.7(3), c = 1280.4(2) pm, α = 64.56(2)°, β = 86.82(2)°, γ = 83.89(2)°, V = 671.1(2) × 106.pm3, Z = 1, R1= 0.0301 for 1965 reflections with I0 > 2σ(I0), iodine molecules with an I–I distance of 268.39(7) pm, slightly longer than in the gas phase, are included in a matrix of db24c8 molecules.

The synthesis and crystal structures of two new salts of chromium(III) with pyridine-2,6-dicarboxylic acid H2Pda (and 2,2’-bipyridyl, Bpy, as a co-ligand) are reported, (HPyz)[Cr(Pda)2](H2Pda)-(H2O)5 (1) and [Cr(Pda)(Bpy)(H2O)][Cr(Pda)2](H2O)2 (2). Both crystal structures contain the octahedral [Cr(Pda)2]− anion with the pincer-type O,N,O-Pda2− ligand. In 1, the pyrazole additive does not act as a ligand, rather it is included as a mono-protonated cation. In 2, both Pda2−, the neutral 2,2’-bipyridyl and water are coordinating Cr3+ in the cation [Cr(Pda)(Bpy)(H2O)]+.

The crystal structure of Hg(C6F4-o-NO2)21 is planar with intramolecular Hg–O coordination whereas those of the polymorphs of Hg(C6F4-m-NO2)22a and 2b have the two aryl rings rotated relative to each other (87° and 59°). At a supramolecular level, both complexes exhibit weak Hg⋯O interactions. Theoretical calculations (B3LYP and MP2) for gas-phase Hg(C6F4-o-NO2)2 and Hg(C6F4-m-NO2)2 molecules predict non-planar conformations in both complexes corresponding to one polymorph of the latter (2a). However, when the supramolecular Hg⋯O interactions are included, using a dimeric model, the calculations more accurately predict the observed structures of 1 and 2b.

A novel tin(II)-compound, bis(η 2 -N,O-2-[4,5-dimethyloxazolyl]-1,1,1-trifluoro-propen-2-olato)tin, Sn II [(Me 2 C 3 NO)(CHCOCF 3 )] 2 ( 1 ), was obtained by reacting Sn[N(SiMe 3 ) 2 ] 2 with 2 M equivalents of the β-heteroarylalkenol, (Me 2 C 3 NO)(CHCOHCF 3 ) ( 2 ). The molecular structures of ligand and the tin derivative were elucidated by single crystal X-ray diffraction and multi-nuclear NMR spectroscopic studies, which confirmed the monomeric nature and fourfold coordination of the tin(II) center with a pseudo-pyramidal geometry. The bidentate chelating mode of 2 imparted intriguingly high air stability to 1 , which together with its high volatility make it an interesting precursor for the chemical vapor deposition (CVD) process. CVD of 1 on gold-coated Al 2 O 3 substrates produced single crystalline SnO 2 nanowires by vapor–liquid–solid growth mechanism. Transmission electron microscopy studies and X-ray diffraction data confirmed the high crystallinity of SnO 2 nanowires possessing an average diameter of 90 nm.

The mononuclear complex, [Co(TAMEN)](ClO(4))(2) (DMSO), containing the Mannich base N,N'-tetra-(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN) as ligand, was synthesized and characterised by conductometric, electronic and infrared spectroscopic properties. The single-crystal X-ray structure show the presence of two well defined units, [Co(TAMEN)](2+) and (ClO(4))(-). The complex cation contains cobalt(II) in the pseudo octahedral environment created by the N(2)O(4) donor set of TAMEN. The cobalt(II) complex have been screened for its cytotoxic activity against three cultured human cell lines established from hepatoma (Hep G2), breast (MCF-7) and lung (A549) cancers as well as on non-tumor bovine kidney (MDBK) cells. The cytotoxic activity of the ligand TAMEN was assessed on one tumor (Hep G2) and one non-tumor (MDBK) cell lines. The cobalt(II) compound was found to decrease in a time- and concentration- dependent manner the viability of tumor (A549, MCF-7, Hep G2) cell lines, while the ligand TAMEN expressed proliferative activity on hepatoma (HepG2) and bovine kidney (MDBK) cells, especially after prolonged incubation.

The two lead(II) coordination polymers [Pb(4,4′-dm-2,2′-bpy)(Dca)(NO3)]n (1) and [Pb(4,4′-dmo-2,2′-bpy)(Dca)(NO3)]n (2) were prepared by treatment of lead(II) nitrate, sodium dicyanamide with 4,4′-dimethyl-2,2′-bipyridine and 4,4′-dimethoxy-2,2′-bipyridine, respectively. Both polymers were characterized by elemental analysis, IR and 1H NMR spectroscopy, thermogravimetric analysis and X-ray crystallography. The coordination polymers can be described as one-dimensional double-chains with Pb(II) centers bridged by Dca and nitrate co-ligands, containing trinuclear rings, [Pb3(L)3(NO3)2(Dca)], and bridging nitrate and Dca co-ligands in cis and trans positions, respectively. The coordination number of the Pb(II) ions in 1 and 2 is seven, with the PbN4O3 coordination polyhedron containing a stereochemically active lone pair of electrons with hemi-directed coordination spheres. The polymer chains form networks via supramolecular interactions that include O⋯O, C H⋯O, C H⋯N interactions, in addition to hydrogen bonding and π–π stacking.

Three new 1:1 complexes of lead(II) with the pincer-type ligand 4′-chloro-2,2′:6′,2″-terpyridine (TpyCl), [Pb(TpyCl)(NO3)2]n (1), [Pb(TpyCl)(ClO4)2]n (2) and [Pb(TpyCl)Br2]2 (3), have been synthesized and characterized by X-ray crystal structure determination as well as spectroscopy and thermal analysis. 1 and 2 are coordination polymers in which the coordination polyhedra are linked via nitrate and perchlorate ligands, respectively, to chains. 3 exhibits a dimeric molecular structure with Pb(μ-Br)2Pb type bridging. In all three compounds the chains and the oligomers are connected to networks via supramolecular interactions which include O···O, C–H···O, C–H···Cl and C–H···Br hydrogen bonding and π–π stacking as well.

[Pb(TpyCl)Cl][Pb(TpyCl)Cl2][PbCl3](CH3OH) (1), a new coordination polymer of divalent lead with the ligand 4′-chloro-2,2′:6′,2"-terpyridine (TpyCl), was obtained as single crystals by the branched tube method. The crystal structure contains three complexes, the cationic [Pb(TpyCl)Cl]+, the neutral [Pb(TpyCl)Cl2] and the anionic [PbCl3]–, which are connected through bridging chlorides and hydrogen bonds to a two-dimensional coordination polymer. In all three complexes, the arrangement around the Pb2+ ion suggests the existence of a stereoactive lone pair.

Salts of transition metal cations complexed by 12-crown-4, benzo-15-crown-5 or 18-crown-6 with I3–, I5– and I82– anions, are synthesized and their crystal structures are determined bysingle X-ray diffraction. The crystal structures of 1, 2 and 3are built up by three different cations with the compositions [Fe(H2O)6(12c4)6]2+, [Zn(H2O)2(b15c5)3]2+, [Zn(H2O)5(18c6)2]2+, and isolated triiodide anions I3–, respectively. Aside from the cations, the isotypic iron and copper compounds (4, 5) contain crystallographically independent V-shaped pentaiodide anions which are linked to dimers by weak interionic contacts. Furthermore, the structures contain centrosymmetric I82– anions. An investigation of possible secondary contacts reveals that the iodine substructure of 4 and 5 consists of essentially isolated octaiodide units.

Three adducts of the N,N′-bidentate aromatic base 4,4′-dimethyl-2,2′-bipyridine (dmbpy) of lead(II) salts, [Pb(dmbpy)2(NO3)2] (1), [Pb(dmbpy)2(ClO4)2] (2) and [Pb(dmbpy)(NCS)2]n (3) have been synthesized and characterized by elemental analysis, IR, 1H-NMR and 13C-NMR spectroscopy and studied by thermal analysis as well as X-ray crystallography. The single-crystal structures of these complexes show that the 6s electrons of lead(II) constitute a stereochemically active lone pair (SALP). The coordination numbers of the PbII ions are eight and seven, respectively. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions.

In the easily accessible salt [(H5O2)(db24c8)]2[Pd2I6(I2)], iodine molecules are catenated in linear anionic chains […I2PdI2PdI2…I–I…]2– which are separated by bulky cations consisting of two (H5O2)+ cations sequestered in dibenzo-24-crown-8 (db24c8) molecules. The new compound is obtained as black single crystals (triclinic, P1, a = 1001.8(2), b = 1185.8(2), c = 1503.7(3) pm, α = 102.97(1), β = 107.65(1), γ = 90.85(1)°, V = 1652.3(5) 106·pm3, Z = 1) from a moist 1:1 dichloromethane/ethanol solution of PdCl2, iodine and db24c8. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The 1:1 (arene)mercury complexes [HgR2(arene)] [R = C6F4-o-NO2, C6F4-m-NO2, C6F4-o-H, C6F5; arene = TMB (1,2,4,5-tetramethylbenzene), PMB (1,2,3,4,5-pentamethylbenzene)] are readily formed when mixtures of the mercurial and arene are crystallised from CH2Cl2 or CH2Cl2/hexane. Analogous 1:1 complexes are also formed from Hg(C6F5)(2) and PhMe, whereas novel 1:2 complexes [HgR2(arene)(2)] result from Hg(C6F4-o-NO2)(2) and PhMe or TMO (1,2,4-trimethoxybenzene) and from Hg(C6F5)(2) and TMO. In the crystalline state, the 1:1 [HgR2(arene)] complexes exist as canted columns of alternating planar HgR2 and arene layers linked by weak (Hg center dot center dot center dot C 3.2-3.5 angstrom) eta(1) or eta(2) pi-arene-mercury interactions. For the TMB (R = C6F4-o-NO2, C6F4-o-H, C6F5) and PhMe (R = C6F5) complexes, the packing of neighbouring columns shows aligned, alternating fluoroarene and arene ring planes resulting in a 2D brick-wall motif with potential supramolecular components (fluoroarene-fluoroarene and fluoroarene-arene stacking). For the TMB complex with R = C6F4-m-NO2 the 2D array is distorted into a herringbone motif by weak C-H center dot center dot center dot O interactions. The 1:2 complex [Hg(C6F4-o-NO2)(2)-(PhMe)(2)] has an analogous mercury environment to the 1:1 complexes, and the packing shows a distinct layer structure of alternating rows of PhMe and HgR2 with two PhMe units per HgR2 unit but with no inter-stack interactions. The TMO complexes have long Hg center dot center dot center dot O contacts (3.2 angstrom.) rather than Hg center dot center dot center dot C and similarly show a layered structure, but in this case, with a single column of alternating HgR2 and pairs of TMO. Theoretical calculations for the 1:2 [HgR2(TMB)(2)] Complexes (R = C6F4-o-NO2, C6F4-m-NO2) are consistent with the findings from the observed crystal structures.

The synthesis of Schiff bases N,N′‐bis(4‐dodecyloxy‐benzylidene‐N‐propyl)‐piperazine (2) and N,N′‐bis‐[4‐(4′‐octyloxy‐benzoic)‐ester‐benzylidene‐N‐propyl]‐piperazine (6) in a multistep process is reported. The intermediates as well as the products were characterized by elemental analysis, melting point and IR, 1H and 13C‐NMR spectroscopy. The complex formation of these Schiff bases with copper(II) perchlorate resulted in disruption of the imino bond and yielded N,N′‐bis(3‐aminopropyl)piperazineperchloratocopper(II) perchlorate, Cu(L)(ClO4)2, where L stands for N,N′‐bis(3‐aminopropyl‐)piperazine. The nature of the complex is established by elemental analyses, IR and Raman spectroscopy and its structure by X‐ray diffraction measurements. The mesomorphic ordering of the ligands have been checked.

Although incongruently melting at 398 °C, single crystals of TaI4 were obtained as a by-product during a reaction which was designed for Rb{Pr6C2}I12. The crystal structure of TaI4 [triclinic, (no. 2); a = 705.9(1), b = 1062.3(2), c = 1072.3(2) pm, α = 79.55(2), β = 89.78(2)°, γ = 75.57(2)°, V = 765.1(5)106 pm3; Z = 2, R1 = 0.042 for I0 > 2σ(I0)] contains tetrameric molecules which consist of two face-sharing dimers of TaI6 octahedra which share a common edge. The Ta-Ta distance in the face-sharing dimers is 297.5(1) pm and may be associated with a single bond. Theoretical calculations exhibit two degenerate HOMOs which are occupied by four electrons; two four-center-two-electron bonds is, therefore, a better description of the metal-metal bonding situation in Ta4I16.

Molecular Complexes and Coordination Polymers of Divalent Mercury with the 4-N-Ligand 6,7-Dimethyl-2,3-di-(2′-pyridyl)-chinoxaline (Dpc) Single crystals of six 6,7-dimethyl-2,3-di-(2′-pyridyl)-chinoxaline (Dpc) complexes of divalent mercury with –CF3, -SCN, -NO3, -I, -Br, and -Cl as the ligands have been obtained mostly by slow evaporation of solutions of the mercuric salts Hg(CF3)2, Hg(SCN)2, Hg(NO3)2, HgI2, HgBr2, or HgCl2 and Dpc. The crystal structures were determined by single crystal X-ray diffraction: [Hg(CF3)2(Dpc)] (1) [monoclinic, P21/c (no. 14), a = 815.7(1), b = 2780.2(4), c = 1036.5(1) pm, β = 99.78(1)°, V = 2316.5(4) 106 pm3, Z = 4, R1 [I0 > 2σ(I0)] = 0.0334], [Hg(SCN)2(Dpc)] (2) [triclinic, (no. 2), a = 817.4(2), b = 1075.8(2), c = 1427.0(3) pm, α = 110.48(2), β = 103.02(3), γ = 94.42(3)°, V = 1128.5(4) 106 pm3, Z = 2, R1 [I0 > 2σ(I0)] = 0.0425], [(HgCl2)2(Dpc)](CH3CN) (3) [triclinic, (no. 2), a = 942.8(1), b = 950.6(1), c = 1486.9(2) pm, α = 80.18(1), β = 79.57(1), γ = 87.73(1)°, V = 1291.3(3) 106 pm3, Z = 2, R1 [I0 > 2σ(I0)] = 0.0469], [HgBr2(Dpc)] (4) [monoclinic, C2/c (no. 15), a = 792.9(1), b = 2411.5(5), c = 1261.5(2) pm, β = 102.11(2)°, V = 2358.5(6) 106 pm3, Z = 4, R1 [I0 > 2σ(I0)] = 0.0354], [HgI2(Dpc)] (5), [monoclinic, C2/c (no. 15), a = 4162.2(17), b = 747.8(2), c = 1509.4(5) pm, β = 111.16(3)°, V = 4369.0(20) 106 pm3, Z = 8, R1 [I0>2σ(I0)] = 0.0547], [Hg(NO3)2(Dpc)](H2O) (6) [monoclinic, P21/c (no. 14), a = 1256.1(2), b = 1257.8(2), c = 1482.1(3) pm, β = 116.44(1)°, V = 2096.6(6) 106 pm3, Z = 4, R1 [I0 > 2σ(I0)] = 0.0414]. The crystal structures of 2, 3 and 5 consist of molecular complexes, those of 1, 4 und 6 exhibit coordination polymers. In all cases, HgII has a characteristic coordination number of, essentially, CN = 2, to different ligator atoms, C in 1, S in 2, Cl, Br, and I in 3-5 as well as N in 6.

In the monohydrate Pr(OOC-Ph-NH2)3(H2O) (1), Pr3+ is nine-coordinate with only oxygen atoms coordinating. Two carboxylate groups are bidentate-bridging, four are tridentate-bridging and there is one coordinating water molecule, hence the coordination number is nine. The chains run along [0 1 0]. In the anhydrous Pr(OOC-Ph-NH2)(OOC-Ph-NH) (2), the central Pr3+ ion is surrounded by six oxygen atoms and two nitrogen atoms in a distorted square antiprism. These polyhedra are connected to each other via two opposite O–O edges to form chains running parallel [0 0 1]. The chains, in which all carboxylate groups are tridentate-bridging, are arranged in a centered rectangular fashion and are further connected via OOC-Ph-NH bridging.

A convenient synthesis of the 1,3-dihydro-1,3,3-tris(perfluoroalkyl)isobenzofuran-1-ols 3a,b was elaborated starting from commercially available phthaloyl dichloride and trimethyl(perfluoroalkyl)silanes (Me3SiRf) 1a,b (Rf=CF3, C2F5) in the presence of a fluoride source (Schemes 1 and 3). In a reaction analogous to alkyl Grignard reagents, double chloride substitution by two perfluoroalkyl groups and subsequent addition of one perfluoroalkyl group with concomitant ring closure led to this new class of compounds (Scheme 2). The syntheses of the alcohols and some alcoholates, as well as of the corresponding trimethylsilyl ethers are described. A combination of special 1D and 2D NMR experiments allowed the assignment of all atoms of the new compounds. The solid-state structure of 1,3-dihydro-1,3,3-tris(trifluoromethyl)isobenzofuran-1-ol (3a) was elucidated by X-ray diffraction methods.

Anhydrous rare earth tris(cinnamates) [RE(cinn)3] (RE = La–Lu, Y and Sc and cinnH = trans-cinnamic acid) were prepared by metathesis in water and by direct reaction of the metal with cinnamic acid in a 1,2,4,5-tetramethylbenzene flux at ca. 200 °C. X-ray crystal structure determinations and X-ray powder data show that, in the solid state, the larger lanthanoids (La–Dy) form an isomorphous polymeric series consisting of homoleptic nine-coordinate metal centres bonded to three chelating and bridging tridentate cinnamates. The late REIII cinnamate (RE = Dy, Ho–Lu, Y) complexes also form linear one-dimensional polymeric chains with all RE metal atoms being seven-coordinate. The cinnamates are either bound tridentate bridging in a μ-η2:η1 fashion, or μ-η1:η1syn-syn bidentate bridging. A structural break occurs at dysprosium which has been characterised in both crystallographic forms, and gives solely the late RE form when precipitated at 80 °C. ScIII cinnamate was also isolated as an analytically pure precipitate which was, again, found to be anhydrous in nature. A structural change was identified by powder XRD between the late REIII cinnamates and ScIII cinnamate.

Complexes of Monovalent Dibenzo-18-crown-6 Cations with Triiodide as Anions The new polyiodides [NH4(db18c6)]2(I3)2 (1), [NH4(db18c6)](db18c6)I3 (2), [Na1/2(db18c6)H2O]2I3 (3), [Rb(db18c6)]I3 (4), [Rb(db18c6)]2(I3)2 (5), [Cs(db18c6)]I3 (6), and [Cs2(db18c6)3][Cs(db18c6)3/2](I3)3 (7) were obtained from reactions of dibenzo-18-crown-6 (db18c6) and iodine with NH4I, NaI, RbI, and CsI. Their crystal structures were determined by single-crystal X-ray diffraction. (1) M = NH4, (5) M = Rb: monoclinic, P21/n, a = 1409,67(8), b = 2211,63(14), c = 1627,16(10) pm, β = 101,030(5)°, Z = 4 (crystal data for M = NH4); (2): monoclinic, Pn, a = 1345,26(14), b = 773,82(4), c = 2095,10(20) pm, β = 94,439(8)°, Z = 2; (3): orthorhombic, Pnaa, a = 931,59(13), b = 2213,3(5), c = 2223,9(4) pm, Z = 4; (4): monoclinic, P21/n, a = 999,50(6), b = 1711,33(10), c = 1517,45(9) pm, β = 99,021(5)°, Z = 4; (6): triclinic, , a = 705,16(9), b = 1137,93(14), c = 1678,90(20) pm, α = 73,719(10), β = 79,782(10), γ = 83,669(10)°, Z = 2; (7): triclinic, , a = 1519,25(6), b = 1702,49(7), c = 2136,41(9) pm, α = 102,641(3), β = 101,989(3), γ = 91,911(3)°, Z = 2. 1 : 1 cations centered by M, [M(db18c6)]+, are found in the structures of (1 – 6). In contrast, the triple decker cation found in (7) is less common. The crystal structures are completed by mostly asymmetrically linear I3− anions.

Five new compounds in the system (NH4)Cl/HgCl2/H2O have been obtained as colourless single crystals, (NH4)Hg5Cl11, (NH4)2Hg3Cl8(H2O), (NH4)4Hg3Cl10(H2O)2, (NH4)2HgCl4(H2O), and (NH4)10Hg3Cl16. In all of these, as in HgCl2 itself, (almost) linear HgCl2 molecules persist with Hg-Cl distances varying from 229 to 236 pm. In (NH4)10Hg3Cl16 there are also tetrahedra [HgCl4] with d(Hg-Cl) = 247 pm present. If larger Hg-Cl distances (of up to 340 pm) are considered as belonging to the coordination sphere of HgII, the structures may be described as consisting of isolated octahedra and tetrahedra as in (NH4)10Hg3Cl16, edge-connected chains as in (NH4)2HgCl4(H2O), edge-connected chains and layers of octahedra as in (NH4)4Hg3Cl10(H2O)2, corrugated layers of edge-connected octahedra as in (NH4)2Hg3Cl8(H2O), and, finally, a three-dimensional network of connected six- and seven-coordinate Hg-Cl polyhedra as in (NH4)Hg5Cl11. The water molecules are never attached to HgII. The (NH4)+ cations, and sometimes Cl− anions, play a role for electroneutrality only.

Rare-Earth-Metal Coordination Polymers: Syntheses and Crystal Structures of Six New Pimelinates, [M(Pim)(PimH)(H2O)](H2O) (M = Ce, Pr) and [M2(Pim)3(H2O)4] (M = Tb, Ho, Er, Tm) The new rare-earth metal carboxylates [M(Pim)(PimH)(H2O)](H2O) (M = Ce (1), Pr (2)) and [M2(Pim)3(H2O)4] (M = Tb (3), Ho (4), Er (5), Tm (6)) were prepared from the reaction of pimelinic acid with CeO2, Pr6O11, Tb4O7, HoCl3, ErCl3 and Tm(NO3)3, respectively. Their crystal structures were determined by single-crystal X-ray diffraction. [M(Pim)(PimH)(H2O)](H2O) crystallize in the monoclinic space group P21/n (no. 14) with a = 909.6(1), b = 870.6(1), c = 2240.5(2) pm, β = 92.30(1)°, Z = 4 (crystal data for M = Ce). The isostructural pimelinate-hydrates [M2(Pim)3(H2O)4] crystallize with orthorhombic symmetry, Pbcn (no. 60), with a = 1392.5(1), b = 902.3(1), c = 2408.8(2) pm, Z = 4 (crystal data for M = Tb). The rare-earth cations have coordination numbers of 10 (1, 2) and 9 (3, 4, 5 and 6), respectively. In the crystal structure of [M(Pim)(PimH)(H2O)](H2O) bidentate and tridentate-bridging carboxylate groups form rather dense structures in which chains are bridged to layers and further to networks. Pimelinic acid molecules fill the channels. In [M2(Pim)3(H2O)4] tridentate-bridging carboxylate groups coordinating to two rare-earth ions lead to dimers that are linked with other dimers to strands. The channels thus formed between the strands are rather small in diameter. They do not contain any non-coordinated water molecules.