Reaction of nitroform with vinylacetic acid

Conclusions The reaction of nitroform with vinylacetic acid has given-methyltrinitrobutyric acid. Some derivatives of this acid have been obtained.Translated from Izvestiya Akademii Nauk SSSR Seriya Khimicheskaya, No. 6, pp. 1351–1353, June, 1967.     

Structure and reactivity of the condensation products of aromatic amines with aliphatic aldehydes

A number of previously undescribed propylidenearylamine dimers have been synthesized by the interaction of propionaldehyde with a series of para-substituted anilines(R=H, CH₃, OCH₃, F, Cl, Br, I) and with-naphthylamine. The structure of the bis-propylidenearylamines has been established by a study of their IR and UV spectra. It has been shown that all the bis-propylidenearylamines, except for bis(propylidene-p-fluoroaniline), have the structure of 2-ethyl-3-methyl-4-arylamino-1, 2, 3, 4-tetrahydroquinolines. The dipole moments of the bis(propylidene-p-R-anilines) have been determined. Comparison of the values obtained with the calculated values indicates that the most favorable molecular conformation of the bispropylidenearylamines is a tetrahydroquinoline half-chain with quasi-equatorial positions for the 4-NHAr and NH groups and an equatorial 3-CH₃ group. In contrast to the bis-ethylideneanilines, we did not succeed in finding other stable conformers for the bis-propylidene derivatives. It has been established that bis (propylidene-p-fluoroaniline) has the 1, 3-bis (p-fluorophenylamino)-2-ethyl-1-hexene structure.For communication VI, see [1].     

Etude de la chloration du polychlorure de vinyle en fonction de sa tacticite

Polyvinyl chloride samples of various tacticity have been prepared and photochlorinated in CCl₄ for 4 hr. The chlorination degree correlates directly with the degree of syndiotacticity. Initial PVC with syndiotacticity about 56 per cent, which can be regarded as alternate sequences of syndiotactic and isotactic diads, is quickly chlorinated. The mechanism of chlorine attack on the macromolecula is directly connected with the stereoregularity.     

New method for the synthesis of macrocyclic compounds

A mixture of isomers corresponding to closing of the ring at the 3 and 4 positions of the thiophene ring is formed during intramolecular acylation of 12-(5-methyl-2-thienyl)-lauryl chloride in a homogeneous medium; the reaction proceeds primarily to favor the formation of the isomer with the larger ring (80%). A method for the synthesis of macrocyclic -alkylcycloalkanones by reductive desulfurization of the corresponding bicyclic ketones, which contain thiophene rings, was developed.See Izv. Akad. Nauk SSSR, Ser. Khim., 2228 (1970) for Communication XI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1467–1472, November, 1970.     

Addition of mercaptans to acetylenic γ-hydroxy ketones

Conclusions Both the nucleophilic and the free radical addition of n-butyl mercaptan to acetylenic-hydroxy ketones (1,1-disubstituted derivatives of 2-pentyn-1-ol-4-one) lead to the formation of the corresponding 1,1-disubstituted derivatives of 2-butylthio-2-penten-1-ol-4-one in 41–65% yield.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1669–1670, July, 1973.     

Transmission of electronic effects of substituents in vinyl esters

To elucidate the transmission mechanism of electronic effects of substituents in vinyl esters on the optical parameters of the absorption bands in the IR spectra, a comparison was made of the frequencies of corresponding absorption bands in vinyl ethers, vinyl esters, alkyl esters of carboxylic acids, ketones, and acid anhydrides. Calculation of the - and -electron structure of the molecules by the Hückel and Del Re approximations was made. The results were compared with the spectral characteristics. The conclusion was reached that the ester oxygen atom in vinyl esters reduces interaction of the carbonyl and vinyl groups, although it is not removed completely. In vinyl esters of aromatic acids the effect of benzene ring substituents is displayed by a change of the -electron structure of the CH₂=CH-O-CO- fragment. In vinyl esters of aliphatic acids the electronic influence of radicals of the acid portion is transmitted by the ester oxygen, mainly inductively, which, in its turn, shows a change in the ability of this atom to conjugate with the vinyl group.The authors express their thanks to Yu. A. Kruglyak for allowing use of the programs for the computation and for helpful advice.     

Spectrophotometric determination of germanium with Catechol Violet and cetyltrimethylammonium bromide

A ternary complex between germanium, Catechol Violet (CV) and cetyltrimethylanunoniuni bromide is proposed for the determination of germanium. The stoichiometric ratio Ge:CV is 1:2. Beer's law is obeyed from 0.1 to 1.0 ppm of Ge. The method is highly selective. Interference from Sn(IV), Fe(III), Bi(III), Cr(VI), Mo(VI), V(V) and Sb(III) in mg amounts is eliminated by extracting the germanium into carbon tetrachloride from 9M HC1 and then stripping into water before the photometric determination.     

Ionotropic reactions of β-sultones

The reaction mechanism of-sultones are discussed; a scheme for the reactivity is proposed. Polyfluoro--sultones can undergo anionotropic reactions of the type Hydrogeneous-sultones under prototropic reactions:     

Characteristics of the glucose isomerase from Streptomyces atratus

The molecular mass (Mr) of highly purified glucose isomerase fromStreptomyces atratus has been determined. The native glucose isomerase, which has affinity for xylose, consists of an oligomeric protein containing 1552 amino acid residues and formed of four subunits. The enzyme is stable in the range of temperatures from 40 to 80°C and at pH values of from 6.0 to 11.0.     

Hemorrhagic action of the venoms of Central Asian snakes

Collective characteristics of the venoms belonging to various taxons of Central Asian snakes, demonstrating levels of toxicity and efficiency of hemorrhagic action, together with proteolytic, esterase, and phospholipase activities, have been obtained. A comparative analysis of the collective characteristics (“portraits”) of the venoms and their changes on degradative treatment has shown that the hemorrhagic action of the venoms of viperine and crotalid snakes is connected with metalloproteins. In contrast to the venoms of the elapids (cobras) the toxicity of the venoms of the viperine and crotalid snakes exhibits a dependence on the hemmorhagic effect and the activity of the metalloproteins causing it.