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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.

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.

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.

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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. [ABSTRACT FROM AUTHOR]

Kinetics of the cleavage of two phosphate diesters, bis(4-nitrophenyl) phosphate and 2-hydroxypropyl 4-nitrophenyl phosphate and a triester, 4-nitrophenyl diphenyl phosphate, in the presence of Mg(ii), Ca(ii) and Sr(ii) were studied in 90% vol. DMSO at 37 °C. The alkaline hydrolysis of the triester was inhibited by all cations, but with both phosphodiesters strong catalytic effects were observed. Potentiometric titrations of metal perchlorates by Bu4N(OH) revealed formation of M2(OH)3+, M(OH)+, M(OH)2and M2(OH)5−species. Rate constants for phosphodiester cleavage by individual species were obtained from analysis of rate–concentration profiles. Observed first-order rate constants in the presence of 1–2 mM Mg(ii) or Ca(ii) in neutral and weakly basic solutions were 108–1011times higher than those for background hydrolysis at the same pH while in water additions of up to 50 mM metal produced <100-fold accelerations. Possible structures of DMSO solvated catalyst–substrate complexes were modeled by DFT calculations with Mg(ii). The increased catalytic activity in 90% DMSO is attributed to stronger association of hydroxide ions and anionic phosphodiesters with metal ions and to preferable solvation of cations by DMSO, which creates favorable for reaction anhydrous microenvironment in the coordination sphere of the catalyst. [ABSTRACT FROM AUTHOR]