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Abstract: Micelle formation in a cetyltrimethylammonium bromide-poly(ethylene glycol)-600 monolaurate-chloroform system in the absence and presence of hydroxybenzylated polyethylenimines (PEI) was studied by dielcometric titration, NMR self-diffusion, light scattering, and kinetic methods. A catalytic effect of mixed micelles on the reaction of 4-nitrophenylbis(chloromethyl)phosphinate with PEI was shown. The catalytic effect depends on the degree of substitution of PEI and composition of a surfactant mixture.

Abstract: Isomeric pyrimidinophanes containing uracil moieties and nitrogen atoms in bridges have been synthesized and characterized by a variety of methods both in solid and in solution. Unambiguous assignment of mutual arrangement of C(4)pyrO groups at different pyrimidine rings in isomers is made by X-ray diffraction. In solutions the arrangement of C(4)pyrO groups of the isomeric pyrimidinophanes results in different dipole moments. Based on dipole moments simulations mutual orientation of uracil units in isomers is analysed. UV-data are discussed in terms of hypo- or hyperchromic effect.

Abstract: Reactions of calixarenes with methylaminoacetaldehyde dimethyl acetal and formalin gave Mannich bases with the calixarene platform. It was found by dielcometric titration that calix[4]resorcinols with acetal groups in the aminomethyl fragment form head-to-head supra-molecular aggregates in chloroform at low concentrations.

Mixed micellization of amphiphilic aminomethylated calix[4]resorcinarenes and phenols, which are their structural units, with the cationic surfactant cetyltrimethylammonium bromide (CTAB) in aqueous 10—70 vol % DMF decreases the critical micelle concentration; the resulting aggregates are larger than those in the CTAB—DMF—water systems. The micellization of CTAB with aminomethylated calix[4]resorcinarenes proceeds in two steps, while its micellization with phenols is a single-step process. The micellization characteristics depend on the structure and hydrophobicity of the amphiphilic compound and the concentration of DMF.

Aggregation and intermolecular interactions of amphiphilic calix[4]resorcinarene (1), aminomethylated calix[4]resorcinarenes (AMC 2—7) with different structures of the upper rim (including the oxazine structure in 6and 7) and hydrophobic substituents on the lower (2—5), upper (6), or both rims (7) in the absence and in the presence of the nonionic surfactant Triton-X-100 (8) and p-nitrophenol (9) in chloroform and 1,4-dioxane were studied by permittivity measurements and 2D ROESY 1H NMR technique. The tendency of amphiphilic derivatives 1—7toward self-aggregation and mixed aggregation with surfactant 8primarily depends on the nature of both the solvent and the polar groups on the upper rim of calixarenes. In chloroform, AMC—8aggregates show interactions of the methyl and methylene groups of the hydrophobic substituents of AMC with the ethyleneoxy fragments of surfactant 8, while in stable intermolecular complexes of 5and 6with compound 9, the methylene groups of the long-chain radicals of the AMC strongly interact with the aromatic protons orthoto the hydroxy group of 9. In 1,4-dioxane, calix[4]resorcinarenes 1and 5are bound in stable solvates, which prevents them from forming aggregates and mixed micelles.

The reaction of 4-nitrophenyl bis(chloromethyl)phosphinate with 2-dialkylaminomethylphenols in toluene solutions of polyethylene glycol 600 monolaurate was studied spectrophotometrically. The effect of structural features of the micellar system on the catalytic effect depends on the nucleophile hydrophobicity. Micellization of the nonionic surfactant was studied by dielectrometric titration and by the kinetic method. The aggregation numbers and the composition of detergent aggregates were determined.

Theoretically, cycloaddition of two molecules of phosphorylated nitrile oxide to C60can give rise to 22 regioisomers. A simple convenient nomenclature was proposed for their classification based on the well-known Hirsh nomenclature. A combination of HPLC, semiempirical quantum-chemical PM3 calculations, and the dipole moment method demonstrated that the equatorial, trans-4(tt), and trans-3(tt) adducts are most probable.

Micelle formation by n-alkyl(2-hydroxyethyl)dimethylammonium bromides in chloroform was studied by dielcometric titration and kinetic method. Increase in the length of the hydrocarbon chain leads to reduced critical micelle concentration. The region of structural reorganization of micelles was determined. n-Alkyl(2-hydroxyethyl)dimethylammonium bromides catalyze phosphorylation of tetrakis(dimethylamino- methyl)calixresorcin[4]arene. The catalytic activity of micelles depends on the hydrophobic properties and concentration of the surface-active substance, as well as on structural features of its aggregates.

AbstractReaction of the sulfuryl diphenol O2S[(t-BU)MeC6H2OH]2(10) with phosphorus trihalides in the presence of amines yielded the phosphites O2S[(t-Bu)MeC6H2O]2PR where R = Cl for 1and R = Br for 2.Treatment of 1with 2,6-dimethylphenol in a halide displacement reaction gave 3(R = OXyl). In a similar diol reaction with O2S[Me2C6H2OH]2(11), the hydrogenphosphonate O2S[Me2C6H2O]2P(O)H (5) formed. A related hydrogenphosphonate O2S[(t-Bu)MeC6H2O]2P(O)H (4) was obtained by hydrolysis of either 1or 2.The phosphonium bromide salt O2S[(t-BU)MeC6H2O]2PPhBr+Br−(7) formed from the bromination of the phenylphosphonite derivative O2S[(t-Bu)MeC6H2O]2PPh (9), the hydrolysis of which yielded the phosphonate O2S[(t-Bu)MeC6H2O]2P(O)Ph (6). A related phosphonium bromide O2S[(t-Bu)MeC6H2O]2PBr2+Br−(8) was prepared by the reaction of the diphenol 10with PBr3in the presence of N-bromodiisopropylamine. All of the cyclic phosphorus derivatives 1–8were characterized by x-ray studies and NMR measurements. All of the compounds lack donor-acceptor interaction that is potentially available via the oxygen atom of the sulfuryl group present as part of the ring system except for 4.For 4, the structure is pentacoordinated with a displacement from a tetrahedral geometry toward a trigonal bipyramid, The ring conformation is a syntwist-boat whereas the others lacking donor coordination reside in an anti chair-like ring arrangement. Solution 31P NMR chemical shifts are in appropriate ranges indicating retention of the coordination geometry that was found in the solid state. Weak P-Br bond strength is suggested to account for formation of the phosphonium bromides 7 and 8 which contrasts with the hexacoordinate structure obtained previously for an analogous chlorophosphorane. Comparisons with similar formulations of cyclic phosphites and phosphates having ring sulfur atoms show that there is a preponderance of donor-acceptor interactions involving sulfur compared to that experienced with the sulfuryl group.

In the investigated 1,2-diaryl-substituted ethanes, the content of the trans and gauche conformers relative to the C-C bond is practically identical; the trans form shows some predominance. In these compounds, the aromatic rings are orientated in parallel and are turned by an average of 120±10‡ relative to the central C-C bond.

Structural indications of direct polar conjugation, lacking in diphenyl and 4,4'-dinitrodiphenyl, were found in 4-nitrodiphenyl.

1.The magnetic-susceptibility ellipsoids of a nitro group attached to an aromatic ring and of a nitrate anion have been determined by measuring the Cotton-Mouton effect. The axis of maximal diamagnetism of the ellipsoids obtained coincides with the normal to the plane in which the bonds are located.2.The significant acoplanarity of the trinitrotoluene molecule in solution has been established by measuring the magnetic and electric birefringences.3.The molecule of p-dinitrobenzene in solution has an anomalously high atomic polarization and a small constant dipole moment.

Conclusions 1.The dipole moment (2.94 D) and the main semiaxes of the polarizability ellipsoid (3.863, 4.173, 1.115 å) of the carbonate group have been determined.2.Based on combined structural studies the C-envelope is the most probable conformation of trimethylene carbonate.

1.The dipole moments of the two kinds of C-O bonds in acetals and their analogs are not identical.2.In formal molecules and the dimethylketal of acetone the C-O-C-O -C chains have gauche-gauche conformation, with the methyl groups lying on different sides of the O-C-O plane.3.The dimethylketal of tetrachlorocyclopentadienone is represented by a mixture of trans-gauche and gauche-gauche conformers.

1.The polarizability ellipsoids of the triphenyl derivatives of group IV elements do not have axial symmetry.2.The effective conformations of the aryl radicals in these molecules correspond to eclipsing of the adjacent bonds.

In the molecules of symmetrically substituted diarylmethanes, the CAr2 grouping has the C2 symmetry with an orientation of the aryl nuclei close to the eclipsing of the bonds of the central atom.

Conclusions The 2,2-dimethyl 1,3-diketones with methyl and aryl radical substituents exist largely as conformations in which the carbonyl group and the C-Me bond are shielded.

1.Dipole moments and polarizability anisotropies have been measured for a series of methyl- and halogen-substituted methanes.2.The nitroradical polarizability is nonadditive under substitution.3.A method has been proposed in which two independent angles of internal rotation are measured and the results compared with data on the Kerr effect and Raleigh light scattering.4.The C(NO2)2 group has C2 symmetry in molecules of symmetrically substituted dinitromethanes. The C(NO2)2 of 1-chloro-1,1-dinitroethane shows this same symmetry.

1,1-Bis(arylthio)ethanes exist in solutions in the form of conformers with trans-gauche and trans-trans conformations of the C-S-C-S-C chain, while geminal disulfones based on them exist in transgauche and gauche-gauche conformations, with the radicals situated on different sides of the plane of S-C-S.

1.When the cyclohexane ring is trans-condensed with a five-membered anhydride ring and a bicyclic system the C-C bonds of the bicyclic system occupy equatorial positions.2.The stereochemistry of the diene synthesis of hexachlorocyclopentadiene with the anhydrides of cis- and trans-3-methyl-4-cyclohexene-1,2-dicarboxylic acids is determined by the configuration of the methyl group.3.The addition of maleic anhydride to the diene system of the anhydride of 1,2,3,4-tetracehlorobicyclo[4.4.0]decadiene-8,9-dicarboxylic acid goes in the trans-position to the bonds of the cyclohexane ring.

1.Dialkyl sulfites in liquids, vapors, and solutions are represented by structures with trans-trans- and trans-gauche-conformations of the chain R-O-S-O-R.2.Diaryl sulfites exist in a trans-gauche conformation.

1.According to the data of the dipole moments, Kerr effects, light scattering, and IR spectra, 1,3-dihalopropanes symmetrically substituted in the 2-position are represented in CCl4 by conformers with trans-gauche and gauche-gauche (with an arrangement of the halogen atoms on different sides of the plane of the carbon atoms) orientations of the X-C-C-C-X chain.2.1, 2,3-Trihalopropanes exist chiefly in a gauche-gauche conformation.

A tensor additive scheme has been devised for the optical polarizabilities of the cations of pyridine, quinoline, and isoquinoline. The additional excess charge in these species leads to a decrease in the vertical component of the optical polarizability while the mobility of the electron cloud in the plane of the aromatic ring is retained. This effect is greater in the N-methyl derivatives than in the protonated forms.

1.The NO2 group of nitroaromatic compounds substituted in theo position is rotated with respect to the ring plane, the rotation being 35° for CH3, 66° for a Cl atom, 65° for a Bratom, and 31° for NO2 substitution.2.Introducing side m-NO2 groups into the molecule ofo-substituted nitrobenzenes increases the acoplanarity of the sterically hindered NO2 group through competitive coupling.

Conclusions 1.Analysis of1H NMR spectra has shown that the thiooxide obtained from the α-oxide of Δ3-carene has the two three-membered rings in the cis-configuration, while the thiooxide obtained from the β-oxide is a trans-isomer.2.Measurements of the1H and13C NMR spectra and the Kerr effect have shown the predominant conformation of the α-thiooxide molecule to be that of the inverted boat. In the case of the β-thiooxide, a conformational equilibrium is established in which the predominant configuration is that of the inverted boat, according to the NMR data, and that of the boat itself, according to the Kerr effect measurements.

1.a-Chloromethylalkyl sulfides exist in solutions in a gauche-conformation.2.The C-O and C-S bonds have axially nonsymmetrical ellipsoids of polarizability.3.In a-chloroethers, the anisotropy of the polarizability of the C-C bond is lowered as a result of interaction with the oxygen atom.

1.The insecticides DDT and 1,1-bis(p-chlorophenyl)-2,2-dichlorocyclopropane have similar conformations in solutions.2.The insecticide DDT and its analogs in solutions have a conformation, in which one aromatic ring eclipses the C-H bond (?=62±3‡), and the plane of the second ring is perpendicular to the Car-C-Car plane (?=85‡).

Conclusions 1.The aryl acetate conformations show a planar ester group, and cis-oriented C=0 and C-0 bonds, the aryl radical being rotated out of the bond plane by 65°.2.In the trifluoroacetates, the aryl radical rotation has diminished to 25°.3.The dipole moments of the ester oxygen atom bonds are not additive in the acetates and their analogs.

Conclusions On the basis of the dipole moments and Kerr constants of trans-3,4,7,7-tetrabromobicyclo[4,1,0]heptane and trans-3,4-dibromo-7,7-dichlorobicyclo[4,1,0]heptane, it was established that the most stable conformation is an anti-boat with a two-faced angle between the planes 2-3-4-5 and 5-6-1-2 of 200–215°.

1.Polarity of 1,4-cyclohexadiene dioxide and its bis-adducts with dihalocarbenes was detected on the basis of an analysis of the electrooptical properties.2.It was established by the method of dipole moments, Kerr constants, and depolarization of the Rayleigh light scattering of derivatives and analogs of bicyclo[5,1,0,03,5]octane that the cyclohexane ring, condensed with two three-membered rings, is nonplanar.

1.The dichloroarsine group has a polarizability ellipsoid with major semiaxes of 10.35, 7.31, and 9.20 å3.2.In phenyldichloroarsine and its p-substituted derivatives the C-C-As unshared electron pair angle is 25 ± 10‡.3.The m-substituted aryldichloroarsines exist as mixtures of the syn and anti forms.

Trisarylselenomethanes exist in a conformation with a gauche orientation of the three Ar-Se groups relative to the C-H bond of the central atom.

Aminobenzoic acids in dioxane have been investigated by dipole moment and Kerr effect methods.m-Aminobenzoic acid exists in a solution mainly (~60 %) in thesyn-form. Inp-aminobenzoic acid, conjugation flattens the pyramidal configuration of the nitrogen atom, which is even more flattened ino-aminobenzoic acid owing to an intramolecular hydrogen bond.

The anisotropy of the magnetic susceptibility of pyridine, in contrast to its optical anisotropy, hardly depends on solvation effects. The mean magnetic susceptibilities of picolines and the anisotropic magnetic characteristics of the Car-CH3 group depend on the position of the methyl group on the ring, while the corresponding electric characteristics are not sensitive to this factor.

1.A comparison of the dipole moments of aromatic compounds with different geminal axes of internal rotation allows one to obtain data on the ratio of the conformers with respect to each bond.2.Monothio-, monoseleno-, and selenothioacetals exist in solution in the form of equilibrium mixtures of the conformers.

1.A method was proposed for analyzing complex conformational equilibria using three physical parameters.2.In solution the trans-4,5-dibromobicyclo[4.1.0]heptanes are represented by equilibrium mixtures of the anti-boat-diequatorial half-chair conformations.

The hydration sphere has a predominant effect on the intramolecular electronic interactions of the anilinium cations evident in their magnetooptical properties.

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