Reaction of Β-arylacryloxiranes with phenyl azide. Synthesis and chemical transformations of Β-phenylamino-Β-arylacrylyloxiranes

The reaction of -arylacrylyloxiranes with phenyl azide by refluxing in dioxane or toluene leads to -phenylamino--aryl-acrylyloxiranes. Epoxypropionyl- and -hydroxypropionyltriazoles are also isolated when the reaction is carried out in the dark without heating. It is shown that -phenylamino--arylacrylyloxiranes undergo cyclization to 3(2H)-furanones in an acidic medium, whereas they are converted to 2,3-dihydro-4-pyridones under basic-catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedineii, No. 8, pp. 1022–1027, August, 1988.     

Study of the rotational isomerism about the C-O bond in six-membered secondary-tertiary diols

We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991.     

The dimer of trifluoromethylthiirene

Conclusion The action of the hexaethyltriamide of phosphorous acid on disulfides containing an ,-dichloro-,,-trifluoroisopropyl group gives the dimer of trifluoromethylthiirene, namely, 2,5-bis(trifluoromethyl)p-dithiine. Oxidation of this dimer by the action of sulfuric acid gives a stable radical-cation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1160–1162, May, 1987.     

Synthesis of some esters of α-acetoxy-Β,Β,Β-trichloroethylphosphonic acid

Summary By the reaction of dialkyl esters of -hydroxy, ,-trichloroethylphosphonic acid and acetic anhydride in the presence of a few drops of sulfuric acid, the dialkyl esters of -acetoxy-,,-trichloroethylphosphonic acid were obtained in high yields.     

Crystallization,melting and spherulitic structure of Β-nucleated random propylene copolymers

The characteristics of crystallization, melting and spherulitic growth of a random propylene copolymer (PRC) containing small amount of ethylene were studied in the presence of a selective -nucleating agent (calcium pimelate). It was established that the products of isothermal and non-isothermal crystallization are very rich in -modification but have mixed polymorphic composition. The formation of -modification may be attributed to -transition on the surface of growing -spherulites resulting in -twin-spherulites. During melting of PRC of -modification, the characteristics observed with -nucleated propylene homopolymers, namely, a -recrystallization of recooled samples and separated melting of non-recooled samples (i.e. the melting memory effect), as well as a -recrystallization leading to a perfection of the structure within the -modification, are also demonstrated. The disturbance of regularity of the polymer chain highly reduces the tendency to -crystallization. In contrast to the observations with propylene homopolymers, the growth rate of -modification (G ) is higher than that of -modification (G ) and no critical crossover temperature can be found (T()=413 K) below whichG >G . The experimental results show that a partial disturbance of chain regularity by incorporation of comonomer units considerably reduces the tendency to -crystallization.This research was supported by the National Scientific Research Fund (OTKA), the author is grateful for it. Thanks are due to Professor Géza Bodor for his help in X-ray diffractometric investigations and to Ms. Tünde Lócska for her prudential technical assistance in the optical experiments.     

Synthesis of homologs of p-phenoxystyrene

Conclusions Homologs of p-phenoxystyrene that had not been described in the literature have been synthesized: -methyl-p-phenoxystyrene, -ethyl-p-phenoxystyrene, ,-dimethyl-p-phenoxystyrene, -methyl-p-phenoxystyrene, and ,-dimethyl-p-phenoxy styrene.     

A DMA study of the suppression of the Β transition in slightly plasticized PVC blends

A new criterion for evaluating different plasticizers the ability of suppression of the transition in plasticized PVC blends. Accordingly, the suppression ability is proportional to the PVC-plasticizer compatibility, expressed either by the critical solution temperature, CST, or by the interaction parameter related to the difference between the solubility parameters of the blend components. The criterion is, however, valid for low plasticizer contents (<5%w/w) only, as long as the transitions are not overlapped by the transitions, shifted towards lower temperatures due to the effect of the plasticizer. For higher plasticizer contents the transition starts to overlap the transition and the suppression ability of the plasticizer depends increasingly on the efficiency of the plasticizer i.e. on the depression of the glass transition temperature of PVC (related to theT _g of the plasticizer). Accordingly, plasticizers with both good efficiency (lowT _g) and compatibility are more effective in the suppression than plasticizers which have only a higher compatibility but also a highT _g (i.e. reduced efficiency).One of the authors, Tiberiu Vilics, thanks the Konferenz der Deutschen Akademien der Wissenschaften; and Volkswagen Stiftung; for financial support for a research fellowship at the Institut für Makromolekulare Chemie, Freiburg. The financial support of the Deutsche Forschungsgemeinschaft (SFB 60) is greatfully acknowledged.     

Effects of medium and chemical modification on thermal characteristics of Β-lactoglobulin

The thermal properties of -lactoglobulin (-LG) were studied by differential scanning calorimetry (DSC) under different medium conditions.pH, neutral salts, protein perturbants, and polyols all affected the DSC characteristics of -LG. Acylation with fatty acids also changed the thermal properties, particularly peak width at half-height. The results suggest that the structural stability of -LG is controlled by non-covalent forces, particularly electrostatic and hydrophobic interactions. Disulfide bonds did not contribute to the thermal response of -LG. Fatty N-acyl-amino acids caused marked increases in thermal stability and decreases in denaturation enthalpy, and additional peaks were observed in the presence of some palmitoyl derivatives.Contribution No. 2310, Centre for Food and Animal Research.We thank D. Raymond for her excellent technical assistance.     

Synthesis of organocyclosiloxanes containing cyanoalkyl groups on the silicon atom

The cohydrolysis of-cyanoethyl- and-cyanopropylmethyldichlorosilanes with dimethyldichlorosilane has been studied and the optimum conditions ensuring the maximum yield of rings containing cyanoalhyl groups have been determined.B is(-cyanoethyl)hexamethylcyclotetrasiloxane,-cyanopropylpentamethylcyclotetrasiloxane, and bis(-cyanopropyl)hexamethylcyclotetrasiloxane have been obtained for the first time and characterized.     

Carbolines

4-Substituted 3, 4-dihydro--carbolines (X–XVI) were obtained by the Beckman rearrangement of oximes of -(indolyl-3)ketones (I–IV, IX) under the action of phosphorus pentachloride in nitrobenzene. 3, 4-Dihydro--carbolines were converted into -carbolines (XV–XVII) on heating with Brown's palladium catalyst in ethylene glycol. Oximes containing the aryl group react on treatment with p-toluene sulfochloride in pyridine with the formation of the arilides of -(indolyl-3)propionic acids.For preliminary report, see [18].     

Direct nitration and acetylation of the furan nucleus of 1-alkyl-2-[Β -(2′-furyl) vinyl]-benzimidazoles

The direct nitration and acetylation of 1-methyl-, 1-ethyl-, and 1-benzyl-2-[-(2-furyl)vinyl]benzimidazoles has given the corresponding 1-alkyl- and 1-benzyl-2-[-(5-nitro-2-furyl)vinyl]benzimidazoles and 1-alkyl- and 1-benzyl-2-[-(5-acetyl-2-furyl)vinyl]benzimidazoles. The UV spectra of these compounds have been recorded and their ionization constants have been determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 832–834, June, 1970.     

Structure and ambiphilic reactivity of indolizines. 1. Isomeric 6- and 8-nitroindolizines

Reaction of bromoacetone with the accessible methyl--nitropyridines has given some 6- and 8-nitroindolizines. In the case of ,'-dimethyl--nitropyridines, both the 8- and 6-nitroindolizines were obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 203–208, February, 1987.     

Quinindines

It is shown that, together with -quinindane-9-carboxylic acid, the condensation of isatin with cyclopentanone in alkaline medium (Pfitzinger reaction) also affords , -dicyclopentylidenecyclopentanone and 3-cyclopentylidene--quinindane-9-carboxylic acid, the structure of which was confirmed by its NMR, IR, and UV spectra.     

PMR detection of carbocation intermediates in the pinacol rearrangement in a superacid

Conclusions The formation of carbocation intermediates in the pinacol rearrangement, namely, - and -hydroxy-substituted carbonium ions, was established by PMR spectroscopy in the case of the transformation of 3,6,9,10-tetramethyl-9,10-dihydrophenanthrene-9,10-diol to 3,6,9,9-tetramethyl-9,10-dihydro-10-phenanthrenone in the HSO₃F-SO₂ClF acid system. The rate of the isomerization of the -hydroxy-substituted cation to the -hydroxy-substituted cation was estimated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2804–2807, December, 1984.     

Calculation of dipole moments in conjugated enamines by LCAO MO method

Quantum-mechanical calculations were performed for a number of -aminovinyl ketones, and their -dipole moments were calculated. The results are compared with experimental values of _exper =_exper- for 12 -aminovinyl ketones, and a linear correlation was obtained between the experimental and calculated values. On the basis of the results obtained, the conformation of the -electron system and the orientation of the substituents were determined.     

Influence of conjugated nitrogenous bases on the spectra and structure of mixed-ligand nickel(II) chelates containing β-diones

The infrared and electronic excitation spectra of a series of new nickel(II) chelates containing an-diimine (or nitrogenous base, enR) and the anion of a-dione (1,3-ketoenol or 1,3-ketoester,H) were obtained in the solid state and in solution. The composition and the overall structure of the new chelates in the solid state depends on ligand concentration, the substituents within the-dionato moiety and the counterion present. The IR and electronic excitation spectra of [Ni(enR)₂ ]NO₃ and [Ni(enR)(O₂NO)] indicate, in conjunction with other physicochemical measurements, bidentate coordination of the ligands, while the spectral shifts reveal replacement of the (O,O)nitrato group by basic solvents. The existence of the nickel(II) in an octahedral environment is confirmed by an X-ray structure analysis of [Ni(dpamH)₂acac]NO₃ · CH₃OH (monoclinic, space groupP2_l/n, a=17.296(1),b=7.462(1),c=21.604(3) å,=95.65(1),Z=4, R=0.0534,Rw=0.0600), where dpamH denotes the 2,2-dipyridylamine.     

Synthesis of alkali and heavy metal dithio- and thiocarbamates based on N-(Β-aminoethyl)piperazine

A series of alkali and heavy metal dithio- and thiocarbamates based on N-(-aminoethyl)piperazine and its derivatives N-(-piperazinoethyl)imides, N-[(-2,5-dimethyl-1-pyrrolyl)ethyl]piperazine, and N-(-salicylideneaminoethyl)-piperazine is prepared. Methods for preparation of dithio- and thiocarbamates based on piperazine are improved. Alkali metal dithio- and thiocarbamates based on piperazines form polymeric complexes with heavy metals.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1524–1528, November, 1989.     

A study of nitrogen- and sulfur-containing heterocycles

The catalytic hydrogenation of N--cyanoacylureas and 1-alkyl-3--cyanoacylureas in the presence of hydrochlorides of aromatic amines has given N--arylaminoacryloyl-, 1-alkyl-3--arylaminoacryloyl-, N--alkyl--arylaminoacryloyl-, and 1-alkyl-3--alkyl--arylaminoacryloylureas. The action of N- -phenylaminoacryloyl- and 1-methyl -3- -phenylaminoacryloylureas of ethanolic hydrogen chloride has given uracil and 1-methyluracil.For Communication IX, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 847–850, June, 1970.     

Transformed steroids. 180. Stereospecific transformation of 17Β-hydroxy-17α-ethynylsteroids into various 17α-substituted 17Β-ethynylsteroids

The use of a dicobalt hexacarbonyl protective group permitted us to carry out the stereospecific conversion of 17-hydroxy-17-ethynylsteroids into branched 17-R-substituted 17-ethynylsteroids (R-OH, OAc, OMe, NCS, and F).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 675–681, March, 1990.