Mixed micelles of cetyltrimethylammonium bromide and poly(ethylene glycol)-600 monolaurate as catalysts of polyethylenimine phosphorylation in chloroform

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. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1359–1365, August, 2006.     

Cotton-mouton constants and spatial structure of pyridiniumethane derivatives and their analogs in aqueous media

A conformational analysis has been performed on 1,2-dipyridiniumethane and 1,2-diisoquinoliniumethane, using data on the Cotton-Mouton effect in water and in methanol. It has been shown that, in comparison with the 1,2-dibenzyl derivatives, in aqueous media, an abnormally high excess of the gauche conformer over the trans conformer is observed, an effect that is attributed to the formation of hydrate bridges.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2766–2771, December, 1991.     

Kerr constants and dipole moments of aminobenzoic acids in dioxane

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.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 859–861, May, 1994.     

Cotton-mouton constants and valency optical scheme for salts of pyridine,quinoline, and isoquinoline

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.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 615–619, March, 1991.     

Axial Site Occupancy by the Least Electronegative Ligands in Trigonal Bipyramidal Tetraoxyphosphoranes(1)

Analogous to the formation of CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Ph)(O(2)C(6)Cl(4)) (1), the new bicyclic tetraoxyphosphoranes CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Et)(O(2)C(6)Cl(4)) (3) and CH(2)[ClC(6)H(3)O](2)P(Ph)(O(2)C(6)Cl(4)) (4) were synthesized by the oxidative addition of the appropriate cyclic phosphines with o-tetrachlorobenzoquinone. For the formation of CH(2)[(t-Bu)(2)C(6)H(2)O](2)P(Ph)(O(2)C(2)Ph(2)) (2), a similar reaction was followed with the use of benzil (PhCOCOPh) in place of o-tetrachlorobenzoquinone. X-ray analysis of 1-3 revealed trigonal bipyramidal geometries and provided evidence for the first series of complexes in the absence of ring strain in which the least electronegative group, ethyl or phenyl, is located in an axial position, in violation of the electronegativity rule. Thus, the two oxygen-containing ring systems occupied two different sets of positions in the trigonal bipyramid (TBP) with the eight-membered rings at diequatorial sites. X-ray analysis of 4 revealed a trigonal bipyramidal geometry with electron-withdrawing chlorine substituents on each ring assumed the more conventional geometry with the rings occupying axial-equatorial positions and the phenyl group located in the remaining equatorial site. The fact that molecular mechanics calculations favorably reproduced the observed geometries suggests that a steric contribution associated with the ring tert-butyl groups for 1-3 is partly responsible in favoring diequatorial ring occupancy for the eight-membered ring. NMR data supported rigid pentacoordinated structures in solution at 23 degrees C. Phosphorane 1 crystallizes in the orthorhombic space group Fdd2 with a = 44.787(5) ?, b = 34.648(8) ?, c = 10.3709(9) ?, and Z = 16. Phosphorane 2 crystallizes in the orthorhombic space group Pna2(1) with a = 20.658(8) ?, b = 10.342(2) ?, c = 19.879(6) ?, and Z = 4. Phosphorane 3 crystallizes in the orthorhombic space group Pcmn with a = 9.807(2) ?, b = 16.632(4) ?, c = 23.355(3) ?, and Z = 4. Phosphorane 4 crystallizes in the monoclinic space group C2/c with a = 35.699(5) ?, b = 12.187(2) ?, c = 14.284(3) ?, beta = 107.08(1) degrees, and Z = 8. The final conventional unweighted residuals are 0.0395 (1), 0.0518 (2), 0.0540 (3), and 0.0868 (4).     

Phosphorylation of polyethyleneimine in the solutions of calyx[4]resorcinolarene and its mixture with the surfactant

Phosphorylation of alkylated polyethyleneimine in chloroform in the presence of alkylated calyx[4]-resorcinolarenes with 2-hydroxyethoxy- and phosphorus-containing substituents and cetyl(3-hydroxypropyl)-dimethylammonium bromide was studied by means of the UV spectrophotometry. It was found that the character and the degree of the effect of calyxarene and its mixture with the surfactant depend on the hydrophobicity of macroring and the ratio of concentrations of components in the solution. The increase in the content of calyxarene and decrease in the concentration of polymer leads to the transformation of the catalytic action into the inhibiting one.     

Inverse Micellar Catalysis of Phosphorylation of Hydroxybenzylated Polyethylenimines

The aggregation in polyethylenimine-chloroform and cetyltrimethylammonium bromide-polyethylenimine-chloroform systems is studied by dielcometric titration. Inverse micelles of cetyltrimethylammonium bromide catalyze the phosphorylation of hydroxybenzylated polyethylenimines in chloroform. The dependence of parameters of the micelle-catalyzed reaction on the structure and concentration of polyethylenimine and on the reaction temperature is studied. The inverse micelles affect the complexation of polyethylenimines with 4-nitrophenol.     

Molecular polarizability and the three-dimensional structure of substituted trinitromethanes

A method is suggested for estimating the assymmetry of molecules based on analysing their polarizability ellipsoids. This method is applied to fluoro-, chloro- and bromo- trinitromethanes and to 1,1,1-trinitroethane. The effective angles of rotation of nitro groups have been determined.