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Two new chlorodiorganotin(IV) dithiocarbamate complexes with general formula {(R2SnCl)dtc} (dtc = R1R2NCS2−, R1 = Bn, R2 = naphtylimide; 3, R = n-Bu; 4, R = Ph) have been prepared from sodium N-[2-(benzylamino)ethyl]naphthalene-1,8-dicarboximide dithiocarbamate 2. The bis-dithiocarbamete 3d (R2Sn(dtc)2, R = n-Bu) was obtained as the thermodynamic product during the titration process (vide infra). All compounds were characterized by mass spectrometry, IR, 1H and 13C NMR spectroscopy. The chlorodiorganotin(IV) dithiocarbamate complexes 3–4 also were characterized by 119Sn NMR spectroscopy and single crystal X-ray diffraction analysis. The crystallographic study of these complexes showed the existence of C H…π, S…π and π…π intramolecular interactions, indicating that the naphthylimide aromatic fragment stabilized the complexes. Complexes 3 and 4 were studied as host for anions (CH3CO2−, F−, H2PO4−) in CDCl3 by UV–Vis and 119Sn NMR spectrometric titrations. The tested anions cause the displacement of the chloride ligand of the metallic centre. The excess of F− or H2PO4− induce the self-assembly of diorganotin(IV) dithiocarbamate to bis-dithiocarbamates R2Sn(dtc)2 (3d) instead of the breaking of the S Sn covalent bond. Quantum mechanical calculations at DFT level (B3LYP/def2-TZVP) were performed to obtain the thermodynamic parameters of the reactions involved in the anion addition to the complexes.

Phase relations in the pseudo-binary systems RFeO 3 -R 2 Ti 2 O 7 (R: Lu, Ho and Dy), RGaO 3 -R 2 Ti 2 O 7 (R: Lu and Er), LuAlO 3 -Lu 2 Ti 2 O 7 and RAO 3 -R 2 Ti 2 O 7 (R: Lu and Yb. A: Cr and Mn) at elevated temperatures in air were determined by means of a classic quenching method. There exist Lu(Fe 1−x Ti x )O 3+x/2 , R(Ga 1−x Ti x )O 3+x/2 (R: Lu and Er) and Lu(Al 1−x Ti x )O 3+x/2 (2/3≤ x≤3/4) having the Yb(Fe 1−x Ti x )O 3+x/2 -type of crystal structure (x=0.72, space group: R 3 m , a(A)=17.9773 and c(A)=16.978 as a hexagonal setting) in these pseudo binary systems. Eighteen compounds R(A 1−x Ti x )O 3+x/2 (R: Lu-Sm and Y, A: Fe, Ga and Al) were newly synthesized and their lattice constants as a hexagonal setting were measured by means of the X-ray powder diffraction method. The R occupies the octahedral site and both A and Ti does the trigonalbipyramidal one in these compounds. Relation between lattice constants for the rhombic R(A 1−x Ti x )O 3+x/2 and the monoclinic In(A 1−x Ti x )O 3+x/2 are as follows, a h ≈5 x b m , c h ≈3 x c m x sin β and a m =3 1/2 x b m , where a h and c h are the lattice constants as a hexagonal setting for R(A 1−x Ti x )O 3+x/2 and a m , b m , c m and β are those of the monoclinic In(A 1−x Ti x )O 3+x/2 . Crystal structural relationships among α-InGaO 3 (hexagonal, high pressure form, space group: P 63/ mmc ), InGaO 3 (rhombic, hypothetical), (RAO 3 ) n (BO) m and RAO 3 (ZnO) m (R: Lu-Ho, Y and In, A: Fe, Ga, and Al, B: divalent cation element, m, n: natural number), the orthorhombic-and monoclinic In(A 1−x Ti x )O 3+x/2 (A: Fe, Ga, Al, Cr and Mn) and the hexagonal-and rhombic R(A 1−x Ti x )O 3+x/2 (R: Lu-Sm and Y, A: Fe, Ga and Al) are schematically presented. We concluded that the crystal structures of both the α-InGaO 3 (high pressure form, hexagonal, space group: P 63/ mmc ) and the hypothetical InGaO 3 (rhombic) are the key structures for constructing the crystal structures of these compounds having the cations with CN=5.

In the structure of the title compound, cooperative C—H⋯O=C, C—H⋯π and offset π–π inter­actions generate supra­molecular nanotubes which accommodate the 2,3-di­chloro­benzene solvent mol­ecules., The asymmetric unit of the title compound, C56H50N6O8S2·3C6H4Cl2, contains two half-mol­ecules of the parent, A and B, which both have crystallographic inversion symmetry, together with three 2,3-di­chloro­benzene mol­ecules of solvation. Mol­ecules A and B are conformationally similar, with dihedral angles between the central naphthalenedi­imide ring and the peripheral naphthalene and benzyl rings of 2.43 (7), 81.87 (7)° (A) and 3.95 (7), 84.88 (7)° (B), respectively. The conformations are stabilized by the presence of intra­molecular π–π inter­actions between the naphthalene ring and the six-membered di­imide ring of the central naphthalenedi­imide moiety, with ring centroid-to-centroid distances of 3.5795 (8) Å (A) and 3.5640 (8) Å (B). In the crystal, C—H⋯O hydrogen bonds link the mol­ecules into infinite supra­molecular chains along the c axis. These chains are inter­connected through C—H⋯π and offset π–π inter­actions, generating supra­molecular nanotubes which are filled by 1,2-di­chloro­benzene mol­ecules.

Four new homoditopic bis[chlorodiorganotin(IV) and triorganotin(IV) dithiocarbamate] complexes derived from naphthalene diimide (NDI) with general formula NDI-[(CH2)2-N(CH2Ph)(CS2SnR2X)]2, 3: R = n-Bu, X = Cl; 4: R = Me, X = Cl; 5: R = Ph, X = Cl; 6: R = X = Me; were prepared from triethylammonium ((1,3,6,8-tetraoxo-1,3,6,8-tetrahydrobenzo[lmn][3,8]phenanthroline-2,7-diyl)bis(ethane-2,1-diyl))bis(benzylcarbamodithioate) 2. All compounds were characterized by IR, as well as 1H and 13C NMR spectroscopy. The complexes 3–6 also were characterized by 119Sn NMR spectroscopy. In addition, complex 3 was further characterized by single-crystal X-ray diffraction analysis. The crystallographic study performed on complex 3 showed that the tin atom has a coordination geometry intermediate between square-pyramid and a trigonal-bipyramidal, with τ value of 0.69. In addition the presence of cooperative C H…π, C H…S, C H…O and S…π intramolecular interactions in the crystal structure of 3 was observed. The interaction of complexes 3–6 with anions (CH3CO2−, F−, H2PO4−) in CDCl3 was studied by UV/Vis, fluorescence and 119Sn NMR titrations. The addition of the foregoing anions to complexes 3-6 lead to the displacement of the chloride ligand at the tin(IV) atom. However, an the excess of F− or H2PO4− induced the self-assembly of complexes 3 and 5 in their corresponding binuclear metallomacrocycles.

Nine mononuclear diorganotin(IV) dithiocarbamate complexes 1–9 with 19-, 20- and 21-membered macrocyclic structures were synthesized from dimethyl, di-n-butyl, and diphenyltin(IV) dichloride and three bis-dithiocarbamate ligands derived from secondary bis-amines having aromatic spacer groups. All compounds were characterized by elemental analysis, mass spectrometry, and spectroscopic methods (IR and 1H, 13C, and 119Sn NMR). Additionally, quantum chemical DFT calculations were performed for the dimethyltin(IV) derivatives in order to model the molecular structures. For one compound series the NMR spectra showed a concentration-dependent behavior in solution, which was analyzed in detail and permitted to postulate the existence of an equilibrium with the corresponding [2+2] macrocycles.

The title compound possesses twofold rotation symmetry, with the planes of the phthalimide moieties inclined to one another by 73.53 (7)° and by 78.62 (9)° to that of the urea unit. In the crystal, mol­ecules are linked via N—H⋯O and O—H⋯O hydrogen bonds, forming a three-dimensional framework structure., The whole mol­ecule of the title compound, C17H10N4O5·2H2O, is generated by twofold rotation symmetry and it crystallized as a dihydrate. The planes of the phthalimide moieties and the urea unit are almost normal to one another, with a dihedral angle of 78.62 (9)°. In the crystal, mol­ecules are linked by N—H⋯O and O—H⋯O hydrogen bonds, forming a three-dimensional framework structure. The crystal packing also features C—H⋯O hydrogen bonds and slipped parallel π–π inter­actions [centroid–centroid distance = 3.6746 (15) Å] involving the benzene rings of neighbouring phthalimide moieties.

A condensation reaction between ethylenediaminetetraacetic dianhydride and p-xylenediamine gave a new chelating cyclophane, 3,10,21,28-tetraoxo-5,8,23,26-tetrakis(carboxymethyl)-2,5,8,11,20,23,26,29-octaaza[12.12]paracyclophane, abbreviated as (32edtaxan)H(4), which has three types of electron-donor groups, i.e., amine, carboxylate, and amide groups. The formation of the cyclophane has been confirmed by a single-crystal X-ray analysis of its Zn(2+) complex, [Zn(2)(32edtaxan)].7.5H(2)O, which crystallized in the monoclinic space group P2(1)/c with a = 19.818(1) Å, b = 13.169(1) Å, c = 18.134(1) Å, beta = 104.491(6) degrees, and Z = 4. Each cyclophane molecule coordinates two Zn(2+) ions and results in the formation of a binuclear chelate molecule. The coordination geometry around each metal ion is distorted octahedral, the donor atoms being two carboxylate oxygen atoms, two amine nitrogen atoms, and two amide oxygen atoms. The new cyclophane exhibited a well-defined fluorescence band at 290 nm with 210 nm excitation. The emission intensity was markedly increased in the Zn(2+) complex, in which the coordination of Zn(2+) ions increases the rigidity of the cyclophane leading to a high fluorescence quantum yield. When the cyclophane was coordinated to Cu(2+) ions, the molar absorptivity of a pi-pi transition band observed at 260 nm was increased by a factor of about 10. Such a large spectral change was not observed for the Zn(2+) and Ni(2+) complexes. In the Cu(2+) complex, the two phenyl rings of the cyclophane are expected to be brought closer, as a result of the coordination of deprotonated amide nitrogens to the central metal ion. This allosterism via ring contraction is responsible for the novel behavior of the absorption spectrum. The emission band of the cyclophane was weakened by coordination of copper and nickel as a result of fluorescence quenching caused by a photo-induced electron transfer.

Dicationic N-methylated at pyridyl or quinolyl moieties derivatives of three isomers of N,N'-bis(pyridyl)pyridine-2,6-dicarboxamide (o-, m-, and p-1) and of N,N'-bis(3-quinolyl)pyridine-2,6-dicarboxamide (4) strongly bind anions in MeCN (log K in the range 3.5-6.5) with pronounced selectivity for Cl(-) and also bind neutral urea and amide guests with log K in the range 1.1-2.8. Crystal structures of the triflate salts of m-1, p-1, and 4 show that amide NH and pyridinium o-CH groups are directed inside the receptor cleft with their four protons forming a circle of radius ca. 2.35 A optimal for inclusion of Cl(-). The binding of anions to these protons is evident from the crystal structure of a mixed triflate/chloride salt of p-1, calculated (DFT/B3LYP 6-31G**) structures of 1:1 complexes of all receptors with Cl(-), and results of (1)H NMR titrations. In the crystal structure of o-1 pyridinium N-Me(+) groups are directed inside the receptor cleft impeding the anion complexation, but calculations demonstrate that simple rotation of pyridinium rings in opposite directions by ca. 30 degrees creates a cavity to which the Cl(-) ion can fit forming 4 hydrogen bonds to amide NH and aliphatic CH groups of N-Me(+). The results of (1)H NMR titrations confirm this type of binding in solution. Anions quench the intense fluorescence of 4, which allows their fluorescent sensing in the muM range. A new methodology for determination of anion binding constants to strongly acidic receptors by inhibitory effects of anions on the receptor deprotonation by an external base has been developed. High affinity and selectivity of anion complexation by dicationic pyridine-2,6-dicarboxamides is attributed to the rigid preorganized structure of receptors, the high acidity of NH and CH groups, and the electrostatic charge effect.

Protonation of an aminoglycoside antibiotic kanamycin A sulfate was studied by potentiometric titrations at variable ionic strength, sulfate concentration and temperature. From these results the association constants of differently protonated forms of kanamycin A with sulfate and enthalpy changes for protonation of each amino group were determined. The protonation of all amino groups of kanamycin A is exothermic, but the protonation enthalpy does not correlate with basicity as in a case of simple polyamines. The sites of stepwise protonation of kanamycin A have been assigned by analysis of 1 H– 13 C–HSQC spectra at variable pH in D 2 O. Plots of chemical shifts for each H and C atom of kanamycin A vs. pH were fitted to the theoretical equation relating them to p K a values of ionogenic groups and it was observed that changes in chemical shifts of all atoms in ring C were controlled by ionization of a single amino group with p K a 7.98, in ring B by ionization of two amino groups with p K a 6.61 and 8.54, but in ring A all atoms felt ionization of one group with p K a 9.19 and some atoms felt ionization of a second group with p K a 6.51, which therefore should belong to amino group at C3 in ring B positioned closer to the ring A while higher p K a 8.54 can be assigned to the group at C1. This resolves the previously existed uncertainty in assignment of protonation sites in rings B and C.

In the title compound, C14H10N2O2, the phtalimide and 2-pyridylmethyl units are almost perpendicular, with an interplanar angle of 85.74 (2)°. In the crystal, molecules are linked by weak C—H...O interactions, forming chains running along the b axis. The packing is further stabilized by offset π–π interactions between adjacent pyridine rings, with a centroid–centroid distance of 3.855 (2) Å.

The alkali metal (Na+, K+, Rb+, Cs+) bis-dithiocarbamate (bis-dtc) salts of N,N′-dibenzyl-1,2-ethylenediamine have been prepared from the reaction of N,N′-dibenzyl-1,2-ethylenediamine with carbon disulfide in the presence of two equivalents of the corresponding alkali metal hydroxide. Additionally, the analogous triethylammonium derivative has been obtained. The resulting compounds have been analyzed as far as possible by elemental analysis, FAB+ mass spectrometry, IR, UV-Vis and NMR (1H, 13C) spectroscopy, and single-crystal X-ray diffraction, showing that the composition of the metal salts can be described by the general formula [{[(H2O)xM-µ-(H2O)yM(H2O)x][bis-dtc]}n] (1, M = Na+, x = 3, y = 2; 2, M = K+, x = 1, y = 2; 3, M = Rb+, x = 0, y = 1; 4, M = Cs+, x = 0, y = 1; 5, M = Et3HN+, x = 0, y = 0). The solid-state and solution studies showed that all alkali metal ions participate in the formation of M–O and cation-π(arene) interactions, while M–S interactions are only observed for the larger alkali metals K+, Rb+ and Cs+. As expected, within the alkali metal group there is a clear tendency for a decreasing number of M–O bonds in favor of M–S and cation–π(arene) interactions, however, only K+ forms a semi-sandwich type complex with η6-coordination.

A protonated cation salt of title compound C36H48N8O12 crystallized in the monoclinic space group with cell parameters a = 11.4721(8)A, b = 23.1049(16)A, c = 21.0730(14)A, β = 99.0040(10)° and Z = 4; the final residual factor was 0.0582 with 9694 reflections. A cyclophane conformation was determinated by an interplay between the ridigidy of amide and phenyl groups and the presence of intramolecular hydrogen bonds and C-H…π interactions.