Hydrogen bonding-based 3D supramolecular architecture of [Cu(CHA)2][TCM]·11H2O

Reaction of Na₄TCM (1) (H₄TCM = tetra[4-(carboxyphenyl)oxamethyl]methane) with [Cu(CHA)](ClO₄)₂ (2)(CHA = 1,3,6,8,11,14-hexaaz atricyclo[12.2.1.1.^8,11] octadecane) in a DMF-water mixture yields [Cu(CHA)]₂[TCM] (3). Structural analysis of [Cu(CHA)]₂[TCM]·11H₂O (3·11H₂O) by single crystal X-ray diffraction reveals strong copper-oxygen bonds between two complex cations and the tetraanion leading to a 3D coordination network (zwitterionic structure), consolidated through additional NH...O=C hydrogen bonding within the cation/anion association. The resulting coordination geometry around a copper atom is a distorted square pyramidal with an oxygen atom of the anionic ligand in the apical position. A 3D supramolecular network is developed in the crystal based only on NH...OC hydrogen bonds between the macrocyclic metallic tecton and the carboxylate groups of neighboring 3D coordinated (zwitterionic) moieties. The pseudotetrahedral TCM^4? tetraanionic ligand induces a diamondoid architecture formed of large distorted adamantanoid cages.      

Spectroelectrochemical Study of 9‐Substituted Acridines with Potential Antitumor Activity

The electrochemical and spectroelectrochemical behavior of 9‐substituted with ? CN and ? COOH acridine N‐oxides with potential antitumor activity was investigated. In SER spectra of the investigated compounds, the ring stretching vibration at 1568 cm^?1 for 9‐CN‐substituted compound respectively 1639 cm^?1 for 9‐COOH‐substituted compound was analyzed. Cyclic voltammograms indicates that the reduction potential ?0.766 V for ? CN substituted compound increase towards ?0.745 V for ? COOH substituted compound. The proposed theoretical method in the electrochemical impedance spectroscopy uses a reference redox dielectrode and a multielectrode containing the compound. To account for the change of electrochemical impedance we have considered two theoretical quantities: a pseudocapacitance and a pseudo inductance. Two possible arrangements of them: in series, respective in parallel can be used like criteria of drug classification.     

Reaction of π-deficient aromatic heterocycles with ammonium polyhalides III. Halogenation of phenothiazin-5-oxide with benzyltriethylammonium polyhalides

Summary Halogenation of phenothiazin-5-oxide with benzyltriethylammonium polyhalides (BTEA) under mild conditions afforded chloro- and bromophenothiazines as well as a few unexpected products e.g. 1,3,7,9-tetrachloro-phenothiazin-5-oxide, 7,3-dibromo-3, 10-diphenothiazinyl tribromide, and 7,3-dichloro-3,10-diphenothiazinyl tetrachloroiodate. A new charge-transfer complex of phenothiazine-5-oxide with bromine is reported.

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Reaktion elektronenarmer aromatischer Heterocyclen mit Ammoniumpolyhalogenverbindungen, 3. Mitt. Halogenierung von Phenothiazin-5-oxid mit Benzyltriethylammoniumpolyhalogeniden

Zusammenfassung Halogenierung von Phenothiazin-5-oxid mit Benzyltriethylammoniumhalogeniden (BTEA) unter milden Bedingungen ergab neben Chlor- und Bromphenothiazinen einige unerwartete Reaktionsprodukte wir z.B. 1,3,7,9-Tetrachlorphenothiazin-5-oxid, 7,3-Dibrom-3,10-diphenothiazinylbromid und 7,3-Dichlor-3,10-diphenothiazinyltetrachloriodat. Außerdem wird über einencharge-transfer-Komplex von Phenothiazin-5-oxid mit Brom berichtet.

     

MICROMECHANICS OF MACROELECTRONICS

The advent of flat-panel displays has opened the era of macroelectronics. Enthusiasm is gathering to develop macroelectronics as a platform for many technologies, ranging from paper-like displays to thin-film solar cells, technologies that aim to address the essential societal needs for easily accessible information, renewable energy, and sustainable environment. The widespread use of these large structures will depend on their ruggedness, portability and low cost, attributes that will come from new material choices and new manufacturing processes. For example, thin-film devices on thin polymer substrates lend themselves to roll-to-roll fabrication, and impart flexibility to the products. These large structures will have diverse architectures, hybrid materials, and small features; their mechanical behavior during manufacturing and use poses significant challenges to the creation of the new technologies. This paper describes ongoing work in the emerging field of research - the mechanics of macroelectronics, with emphasis on the mechanical behavior at the scale of individual features, and over a long time.     

Direct fluorescent detection of chromatographically separated amino-acids by means of 9-isothiocyanatoacridines

A new method is presented for fluorescent detection of amino-acids separated on silica gel R plates, by spraying with a 0.1% solution of 9-isothiocyanatoacridine derivatives in dichloromethane or benzene, heating and examining in ultraviolet light at 254 and 336 nm. This method is useful for routine analysis owing to its selectivity and sensitivity.     

The crystal and molecular structure of the 2,4,6,8 tetra-t-Bu-phenothiazine 0.5 benzene adduct

The crystal structure of 2,4,6,8-tetra-t-Bu-phenothiazine 0.5C₆H₆ (Pnma space group, a=11.685, b=25.593, c=10.339) shows short intermolecular t-Bu(CH₃)Ph and CH₃CH₃ contacts which allow the formation of well defined channels along the a direction. These channels host one benzene molecule for each pair of phenothiazine molecules. AM1 molecular orbital calculations suggest that there is a strong coupling of the t-Bu groups rotations and the folding of the ring and this in turn makes the phenothiazine skeleton to be less folded than expected from the presence of four electron donating substituents.     

Synthesis of new bis(2,4‐dimethyl‐5‐amino‐benzo[b][1,8]‐naphthyridines) and bis(benzo[b][1,8]naphthyridones) linked with methylene linear chain

The preparation of novel alkyl monobridged 2,4‐dimethyl‐5‐amino‐benzo[b][1,8]naphthyiridine and benzo[b][1,8]naphthyridone derivatives by phase transfer catalysis is reported.     

"Inverse sodium hydride": a crystalline salt that contains H(+) and Na(-)

A crystalline salt has been synthesized that contains H(+) and Na(-) rather than the usual hydride oxidation states of H(-) and Na(+). The key is irreversible encapsulation of H(+) within the cage of 3(6)adamanzane (Adz). The internal proton is kinetically inert to reduction by Na(-) in solution in NH(3)-MeNH(2) mixtures. Synthesis of the sodide is accomplished by a metathesis reaction between Na and AdzH(+)X(-) in which X(-) is a sacrificial anion such as glycolate, isethionate, or nitrate. Reduction or deprotonation of the sacrificial anion forms insoluble byproducts and AdzH(+)Na(-) in solution. After solvent removal, the sodide is dissolved in dimethyl ether and transferred through a frit into a separate chamber for crystallization. The compound was characterized as the sodide by analysis, NMR spectra, and optical absorption spectroscopy.     

Supramolecular synthesis through dihydrogen bonds: self-assembly of controlled architectures from NaBH4 x poly(2-hydroxyethyl)cyclen building blocks

A systematic investigation of molecular structures/supramolecular organization relationships in dihydrogen-bonded complexes comprising NaBH4 and poly-2-hydroxyethyl-cyclen (poly-HEC) building blocks is reported. Like in the prototype compound 1, a (NaBH4-poly-HEC)2 dimeric arrangement has been found in the analogous structures 3 and 5, but not in compound 2, which lacks dihydrogen bonds. The exact connectivity of the dimers is determined by a complex interplay of noncovalent interactions such as OH...HB dihydrogen bonds, OH...O conventional hydrogen bonds, Na-O and Na-N coordinative bonds, and dispersion interactions. The persistent recurrence of this general supramolecular motif permits controlled assembly of extended networks with desired architectures, by the use of appropriate spacers for linking the dimers, as demonstrated by the solid-state structure of 7. Additionally, the intrinsic solid-state reactivity of these dihydrogen-bonded networks makes this approach a promising strategy for the rational construction of functional extended covalent solids.