V. V. Bykova

The Molecular and Supramolecular Structure of Metalloorganic Lyotropic Mesogens

Abstract On the basis of data in literature and those obtained from our experiments we have analysed the influence of metal in the structure of rod-like and discoid amphiphilic molecules on their lyotropic mesomorphism.

Mesomorphism and Glass Formation of Phthalocyanine Metal Complexes with Bulky Substituents

This paper deals with the synthesis of phthalocyanine complexes, containing four oligo(oxyethylene)-, oxybenzene-, esther of p-oxybenzoic acid or p-oxyazobenzene side chains terminated by a bulky trityl substituent. Their purity was established by column chromatography and by satisfactory elemental analysis. The structures of resultant phthalocyanines were characterized by nuclear magnetic resonance (NMR), fast atom bombardment mass spectroscopy (FAB-MS), ultraviolet-visible (UV-VIS) and infrared (IR) spectroscopy and their phase transitions were studied by polarizing optical microscopy. Some of these complexes exhibit enantiotropic mesomorphic properties and transition into glass state on cooling. The glass appearance is influenced not only by side chains’ structure, but also by the nature of metal.

Lyotropic Phase Behaviour of Phthalocyanine Derivatives in Apolar Organic Solvents

Abstract Copper (II) and nickel (II) complexes of 2,3,9,10,16,17,23,24-octa(dodecyloxy)phthalocyanine (1a, 1b) and copper (II) complex of 2,9,16,23-tetra(decy1thio)phthalocyanine (1c) have been synthesized and their liquid crystalline properties have been studied. It was established, that 1a-c possess both thermotropic and lyotropic (with apolar organic solvents) mesomorphism. Lyomesomorphism exhibited by compounds can be attributed to chromonic type.

Induction of Mesomorphic Properties in Poly(propylene imine) Dendrimers and their Model Compounds

The lyotropic phase behaviour of selected dendrimers with non-mesomorphic peripheral units, i.e. decyloxybenzoyl substituted poly(propylene imine) dendrimers as well as model compounds of their main parts, i.e. decyloxybenzoyl substituted alkylamines and also derivatives of 1,4,7-triazacyclononane, has been studied. For the first time, the induction/variation of mesomorphic properties in binary systems of these dendrimers or of related model compounds with suitable organic solvents has been established.

Synthesis and Mesomorphic Properties of Substituted Pyrazinoporphyrazines

Tert-butylsubstituted pyrazinoporphyrazines (Ia–Id) and octacarboxypyrazinoporphyrazine (II) were synthesized. The structure of these compounds was determined using elemental analysis, IR and UV-Vis absorption spectroscopy. All synthesized compounds do not exhibit thermotropic mesomorphism. In this work we induced an enantiotropic mesophase due to charge transfer (CT) interactions in mixtures of compounds Ia–Id with a strong electron acceptor 2,4,7-trinitrofluorenone (TNF). The computer simulation of water systems of polar octacarboxypyrazinoporphyrazine (II) was carried out. The simulation shows that compound II does not possess mesomorphic properties in binary systems (lyotropic mesomorphism).

Synthesis and Induction of Mesomorphic Properties of Tetrabenzoporphine Derivatives

Zinc complexes of meso-alkyl-substituted tetrabenzoporphines and their aza-derivatives have been synthesized using the interaction of phthalimide or its derivatives with zinc salts of the carboxylic acids. The porphyrin-ligands were obtained on the basis of the above mentioned compounds. The spectral and mesomorphic properties of the synthesized compounds were studied.

Electrostatic interactions in micellar solutions of sodium n-alkyl sulfates and applicability of the poisson-boltzmann equation for their calculation

By the example of four even members in a homologous series of sodium n-alkyl sulfates (decyl-, dodecyl-, tetradecyl-, and hexadecyl sulfate) and with the use of the Debye-Hueckel theory of strong electrolytes the parameters are calculated that determine electrostatic interactions in micellar solutions of surfactants. Calculation results for the Gibbs electrostatic energy of micellization are compared to those obtained from one of the approximate solutions of the Poisson-Boltzmann equation and also to the results of its numerical integration for spherical micelles. Applicability conditions of the Debye-Hueckel theory are determined with respect to the micelle concentration and size and the number of carbon atoms in a surfactant molecule. It is shown that the Debye-Hueckel theory in the proposed version enables an efficient and quite accurate calculation of all electrostatic properties of micelles and ionic micellar solutions for surfactants with a number of carbon atoms in a molecule starting from 10 and more and at concentrations up to 0.15 mol/dm3.

The Influence of the Structure of Tetra(4-Sulphophenyl)Porphin Derivatives on Their Lyotropic Mesomorphism

Abstract Tetra (4-sulphophenyl)-β-octamethyl-porphin has been synthesized with the object of studying how the structure of the macrocycle, the type and position of the substitutes, and the oharacter of the metal-complex generator influences the lyotropic mesomorphism. Its spectral properties and lyotropic mesomorphism in water-ammonia and water-NaOH systems have been studied.

Nucleophilic Substitution in 4-Bromo-5-nitrophthalodinitrile: VI. 4-Dimethylphenoxy-5-nitrophenoxyphthalodinitrile and the Copper Phthalocyanine Derived from It

Abstract4-(3,4-Dimethylphenoxy)-5-(4-nitrophenoxy)phthalodinitrile was prepared by stepwise nucleophilic substitution of bromine and then the nitro group in 4-bromo-5-nitrophthalodinitrile by the substituted phenoxy groups and was converted to the corresponding octasubstituted copper phthalocyanine by the reaction with copper acetate. The spectroscopic and mesomorphic properties of the resulting complex were studied. It exhibits thermotropic mesomorphism and forms an M phase in the range 85-155°C.

Influence of Meso-Substituted Porphyrins Molecular Structure on Their Mesogenity

The study of 27 new meso-substituted free-base and metal complexes of tetraphenylporphyrins with substitution by alkoxygroups (from -OC4H9 to -OC16H33) in para-, meta-, or ortho-position has been carried out. Out of 11 synthesized free-base alkoxysubstituted tetraphenylporphyrins – 4 possess mesomorphic state of columnar type and 1 – lyotropic mesomorphism in binary systems with toluene, benzene or chloroform. The important role of substituents position in phenyl rings of porphyrins was determined. It was established, that metal complexes (Cu, Ni, Zn, Ag, Pd, SnCl2, ZnOAc, VO) of mesogenic free-base porphyrins does not display liquid crystal properties.