Micellar size, shape and counterion binding of N-(1,1-Dihydroperfluoroalkyl)-N,N,N-trimethylammonium chloride in aqueous solutions

Under the limiting conditions, light-scattering method was applied to determine the size and shape of fluorinated micellar structure in aqueous solution. The hydrodynamic radii (r _h) of molecular aggregates were investigated for four amphiphiles with different alkyl chain length: N-(1,1-dihydroperfluorooctyl)-, N-(1,1-dihydroperfluorodecyl)-, N-(1,1-dihydroperfluorododecyl)-, and N-(1,1-dihydroperfluorotetradecyl)-N,N,N-trimethylammonium chloride by dynamic light scattering. Size of these molecular aggregates drastically increased with increasing carbon number of alkyl chain and the concentration. For example, the r _h values were 35, 63, 95, and 136 nm for C8, C10, C12, and C14 of the alkyl chain, respectively, at the concentration of 15× critical micelle concentration (cmc) and at 298.2 K. On the other hand, the mean radius of gyration (r _g) and the apparent molecular weight of these aggregates were measured using static light scattering. The r _g value was found to be 34, 73, and 125 nm for C8, C10, and C12 of the alkyl chain, respectively, at the same condition above. The shape of aggregate was analyzed by comparing the dependence of r _g/r _h with theoretical values. The plots of r _g against r _h almost corresponded with the theoretical line of oblate ellipsoid (disk-like), and which was also expected from calculation of packing parameter value. The measurement for chloride ion activity was made by a chloride ion selective electrode to know the degree of counterion binding to the aggregates, whose values increased with increasing total concentration and with the carbon number of alkyl chain. The chloride ion binding to aggregates neutralized cationic head groups under their electrostatic repulsion and partly promoted the growth of aggregates.     

Efficient resolution of 2,2'-dihydroxy-1,1'-binaphthyl by inclusion complexation with chiral N-(3-chloro-2-hydroxypropyl)-N,N,N-trimethylammonium chloride

The complete resolution of 2,2[prime or minute]-dihydroxy-1,1[prime or minute]-binaphthyl into its enantiomers by inclusion complexation with a commercially available derivative of choline, is reported. The two enantiomers are recovered in >99% ee from the inclusion complexes by simple dissolution in a diethyl ether-water medium and the resolving agent can be recycled.     

Synthesis of some N-(4,5,5-trisubstituted-Δ2-1,3,4-thiadiazolin-2-yl)-N,N′-dimethylureas

The synthesis of some N-(4,5,5-trisubstituted-Δ²-1,3,4-thiadiazolin-2-yl)-N,N′-dimethylureas is described.     

A Simple,Efficient Synthesis of N6-[bis(ethylamino) methylene]-N2-[(1,1-dimethylethoxy)carbonyl]-lysine (Boc-diethylhomoarginine)

The synthesis of N6-(bis(ethylamino)methylene]-N2-[(1,1-dimethyl ethoxycarbonyl] lysine (Boc-diethylhomoarginine) by regiospecific amidination of lysine with (ethylamino) (ethylimino)-methanesulfonic acid (2) is described.     

Dodecacarbonyltriosmium catalysed formation of bis(4-N,N-dimethylaminophenyl)methane from N,N-dimethylaniline

Os₃(CO)₁₂ catalyses the conversion of NMe₂Ph to (4-NMe₂C₆H₄)₂CH₂ and NHMePh in refluxing N,N-dimethylaniline. This reaction is similarly catalysed by H₄Os₄(CO)₁₂, while (4-NHMeC₆H₄)₂CH₂ may be obtained from NHMePh. In this case, however, NMe₂Ph and NH₂Ph are also formed, and after longer reaction times mixed products of type (4-NRR′C₆H₄)₂CH₂ (R or R′ = H or Me) are obtained. The formation of H₃Os₃(CH)(CO)₉ indicates methyl transfer from nitrogen to osmium which may be a key step in the catalysis, but it does not appear that clusters are essential since Fe(CO)₅ and Cr(CO)₆ are also weakly active.     

N-(2,6-Dihalobenzoyl)-N′-pyrimidinylharnstoffe

N-(2,6-Dichlorobenzoyl)- and N-(2,6-difluorobenzoyl)-N-pyrimidinylureas3b–3n have been synthesized by reaction of the corresponding aminopyrimidine derivatives with 2,6-dichlorobenzoyl isocyanate or 2,6-difluorobenzoyl isocyanate. The insecticidal activity of compounds3b–3n has been evaluated.

     

Preparation and polymerization of N-(1,1-dimethyl-3-hydroxybutyl) acrylamide and N-(1,1-dimethyl-3-hydroxybutyl)methacrylamide

The syntheses of N-(1,1-dimethyl-3-hydroxybutyl)acrylamide and the corresponding methacrylamide by reduction of the oxobutyl acrylamides are described. These monomers are colorless liquids which are soluble in water and many organic solvents. They polymerize readily to form homopolymers and copolymers with other vinyl monomers. The preparation of polymers containing these repeating units by reduction of polymers of diacetone acrylamide and diacetone methacrylamide is also described.     

Unusual reactions of N-(trifluoromethylsulfonylimino)di-and-trifluoromethanesulfinimidoyl chlorides

N-(Trifluoromethylsulfonylimino)di-and-trifluoromethanesulfinimidoyl chlorides RS(=NSO₂CF₃)Cl (R = CF₃, CHF₂) react with potassium fluoride in 1,2-dimethoxyethane with formation of the corresponding N,N′-bis(trifluoromethylsulfonyl)fluoromethanesulfinimidamide potassium salts RS(=NSO₂CF₃)NSO₂CF₃ ^?K. Analogous methanesulfinimidoyl and fluoromethanesulfinimidoyl chlorides (R = CH₃, CH₂F) fail to react with KF under similar conditions. Treatment of trifluoromethanesulfenamides CF₃SNR₂ with N,N-dichlorotrifluoromethanesulfonamide CF₃SO₂NCl₂ leads to N,N-disubstituted N′-(trifluoromethylsulfonyl)trifluoromethanesul-finimidamides CF₃S(=NSO₂CF₃)NR₂. The reaction of N,N-dimethyl-N′-(trifluoromethylsulfonyl)trifluoromethanesulfinimidamide (R = CH₃) with gaseous hydrogen chloride in diethyl ether gives sulfinimidoyl chloride CF₃S(=NSO₂CF₃)Cl which could not be obtained by imination of CF₃SCl.     

Synthesis and Crystal Structure of N3-（Dimethyl- pyrimidine）-N4-（tri-O-acetyl-xylosyl） Thiourea

The crystal structure of the title compound （C18H24N4O7S, Mr = 440.47） was prepared by the condensation of 2,3,4-tri-O-acetyl-β-D-xylopyranosyl isothiocyanate with 4,6-dimethylpyrimidin-2-amine and structurally determined by single-crystal X-ray diffraction. The crystal belongs to the monochnic system, space group P2 1 with a = 7.5500（17）, b = 10.498（2）, c = 14.208（3） A, β = 99.929（4）°, V = 1109.2（4） A^3, Z = 2, Dc = 1.319 g/cm^3,μ = 0.191, F（000） = 464, Flack = 0.00（15）, R = 0.0684 and wR = 0.1103. In the crystal structure, the xylose ring adopts a ^4C1 chair conformation. Due to the hydrogen bonding interaction between N（4）-H（4A） and N（1）, the pyrimidine ring is well positioned.     

N-(3,4-diarylthiazolyl-2)-N′-benzalhydrazines

Reaction of 4-arylthiosemicarbazones of aromatic aldehydes with-bromoacetophenone gives N-(3, 4-diarylthiazoyl-2)-N-benzalhydrazines.     

Electronic Structure and Magnetic Properties of Clusters with (μ-1,1-N3) Bridges

Quantum-chemical calculations and a generalized angular overlap model were used to demonstrate that the electronic structure of N^– ₃ anions is favorable for the development of ferromagnetic properties in polynuclear complexes whose structural elements are planar binuclear fragments of the M(N₃)₂M type characterized by a broad range of M–N–M angles (95°–105°). Analysis of the known experimental data points to the correctness of the theoretical views and demonstrates the ferromagnetic stability of complexes of this type to the deviation of the N₃ ligands from the plane of the MN₂M ring.