Synthesis of water-soluble lithium,sodium, potassium,and cesium salts of (E)-2-[4-methoxy(3,4-dimethoxy)-benzylideneamino]-2-alkyl(aralkyl)acetic acids

A convenient method of preparative synthesis of water-soluble lithium, sodium, potassium, and cesium salts of (E)-2-[4-methoxy(3,4-dimethoxy)benzylideneamino]-2-alkyl(aralkyl)acetic acids via reaction of anisic or veratric aldehyde with natural amino acids (glycine, L-valine, L-leucine, L-isoleucine or Ltryptophan) in the presence of lithium hydride or carbonates of sodium, potassium, or cesium in boiling methanol was developed.     

Synthesis of 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carboxylates derived from natural alcohols,thymol, and its synthetic analogs

Esters derived from 5-phenyl-, 5-(4-methylphenyl)-, and 5-(2,5-dimethylphenyl)-1,2-oxazole-3-carboxylic and 4,5-dichloro-1,2-thiazole-3-carboxylic acids and some natural alcohols (L-menthol, grosshemin), thymol, and synthetic analogs of the latter (4-tert-butylphenol, 4-tert-octylphenol, 2-tert-butyl-4-methylphenol) were synthesized by reactions of the corresponding alcohols with acid chlorides.     

DDA simulations of light scattering by small irregular particles with various structure

We present DDA investigations of light scattering by irregular particles whose size is comparable with wavelength. We consider four types of randomly irregular particles: strongly damaged spheres, rough-surface spheres, pocked spheres, and agglomerated debris particles. Each type of particle is generated with a well defined algorithm producing an ensemble of stochastically different particles that have a common origin. The different types of irregular particles produce different angular dependencies of intensity and linear polarization degree. Transformation of phase curves of intensity and polarization with changing size parameter for irregular particles tends to be more monotonic, unlike spheres. We find that the magnitude of the negative polarization branch (NPB) tends to shrink as particle absorption increases; whereas, the maximal value and position of the positive polarization branch tends to increase. The most frequently observed shape of the negative polarization at small phase angles is asymmetric with a shift of the minimum position towards the angle of polarization sign inversion. All types of considered irregular particles reveal such asymmetry at x<10. Symmetric negative polarization branches occur seldom. The necessary conditions for their appearance are a relatively large size parameter x?10 to 12 and low absorption.     

Synthesis of esters of <Emphasis Type="Italic">m</Emphasis>-C(7)-<Emphasis Type="Italic">iso</Emphasis>-propylcarboran-C(1)-carboxylic acid,natural terpene alcohols,and plant phenols

Previously undescribed esters 1b-21b were prepared by reaction of cetyl alcohol 1a, terpene alcohols 2a-16a, plant phenols 17a-19a, and alcohols 20a and 21a with m-C(7)-iso-propylcarboran-C(1)-carboxylic acid.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 388–392, September–October, 2004.     

Statistical theory of microdeformation of polycrystals IV

We shall refine the theory of microdeformation of polycrystals proposed earlier. The localization of glide and stress relaxation in plastically deformed grains along with the nonuniformity of the stress state is studied by the construction of a microdeformation curve. Laws of deformation hardening in the domain of microdeformation of polycrystals of solid solutions with fcc and bcc lattices are studied experimentally. Good agreement between theory and experiment is obtained.     

Halogen-containing Aromatic Azomethines Derived from Vanillin and Vanillal Esters

Vanillin and vanillal esters were reacted with 4-bromoaniline and 1-bromo-2-naphthylamine in methanol to obtain the corresponding halogen-containing azomethines.     

Trimethylsilyl-1,3,4-oxadiazoles—new useful synthons for the synthesis of various 2,5-disubstituted-1,3,4-oxadiazoles

The reactivity of 2-aryl-5-trimethylsilyl-1,3,4-oxadiazoles toward different types of electrophiles was investigated. These silanes readily react with chlorine, bromine, aliphatic acyl chlorides, 2-nitrobenzenesulfenyl chloride, and some reactive isocyanates affording the corresponding substituted 1,3,4-oxadiazoles. The reactions with carbonyl compounds proceed only in the presence of F⁻ anions.     

Synthesis,film-forming properties,and thermal and light sensitivity of <Emphasis Type="Italic">N,N′</Emphasis>-bis[4-hydroxy(alkoxy,acyloxy)-3-alkoxyphenylmethylidene]benzene-1,4-diamines

Previously unknown E,E-isomeric Schiff bases were synthesized by reaction of p-phenylenediamine with 4-hydroxy-3-methoxybenzaldehyde, 3-ethoxy-4-hydroxybenzaldehyde, and their O-alkyl and O-acyl derivatives in anhydrous methanol. Film-forming properties and thermal and light sensitivity of the products were studied.     

Synthesis of 3-alkoxy-4-acyloxyphenylmethylene(phenyl)amines

Previously unknown E isomers of azomethines (Schiff bases) were synthesized from the vanillin and vanillal esters by the reaction with aniline.     

Synthesis of 1,3- and 1,4-bis-methoxy- and ethoxy-4-(m-carborane-C-methanoyloxy)phenylmethylene- and phenylmethyl]phenylenediamines

1,3- and 1,4-bis[3-methoxy and ethoxy-4-(m-carborane-C-methanoyloxy)phenylmethylene]phenylenediamines were synthesized from the vanillin and vanillal m-carborane-C-carboxylates by the reaction with 1,3- and 1,4-phenylenediamines in anhydrous methanol. Reduction of the title compounds with Na[BH(OAc)₃] in benzene yielded 1,3- and 1,4-bis[3-methoxy- and ethoxy-4-(m-carborane-C-methanoyloxy)phenylmethyl] phenylenediamines.