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1.
ΔE T N values for 2-pyrrolidinone and N-methylbenzenesulfonamide solvent systems, in which the solvents were benzyl alcohol, 1,4-dioxane and hexamethylphosphoric triamide, were determined over the whole mole fraction range. The study was carried out at 30 and 50°C. The ΔE T N values were positive for all of these systems, with the exception of the 2-pyrrolidinone-hexamethylphosphoric triamide system, which was slightly negative. The results are discussed in terms of intermolecular interactions and preferential solvation.  相似文献   

2.
The reactions of 3-chloropropylphosphonates, 3-chloropropylthiophosphonates, or 3-chloropropylphosphinates with 2-aryloxyethylamines or N-phenylpiperazine afford the corresponding 3-(2-aryloxyethylamino)propylphosphonates and -phosphinates or 3-(4-phenylpiperazin-1-yl)propylphosphonates and -phosphinates. The compounds obtained exhibit -adrenolytic and hypotensive activities, the latter being found to depend on the substituents at the P atom.  相似文献   

3.
It has been shown possible to introduce an -hydroxyethyl group trans-stereospecifically into position 3 of 4-methyl-1-(-methyl-benzl)azetidin-2-one. The stereochemistry of the asymmetric centers C(3), C(3), and C(4) of the diastereoisomers of the 3--hydroxyethyl derivative obtained in larger amount and of the corresponding three adjacent chiral centers C(8), C(6), and C(5) in thienamycin are the same.For part 2 see [1].M. V. Lomonosov Moscow State University, Moscow, 119899. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 254–257, February, 1995. Original article submitted December 14, 1994.  相似文献   

4.
In the interaction of 2--clzlorobenzylidenehydrazino-4-ethoxycarbonylthiazole with nucleophiles, two competing reactions take place. 1) nucleophilic replacement of the chlorine atom to form the corresponding substitution product; 2) elimination of a hydrogen chloride molecule, concluding in cyclization of the intermediate nitrilimine to form 3 phenyl-5-ethoxycarbonylthiazolo(2, 3-c]-1, 2, 4-triazole. The direction taken by the interaction depends on the nature of the nucleophile and is determined primarily by the ratio of basicity and nucleophilicity of the agent.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, 256–259, February, 1994. Original article submitted December 30, 1993.  相似文献   

5.
Abstract

Both AB and BA block copolymers of α-methylstyrene (αMeSt) and 2-chloroethyl vinyl ether (CEVE) were synthesized by the sequential living cationic polymerization initiated with the HCl-CEVE adduct (1a)/SnBr4 system in CH2Cl2 at -78°C. αMeSt-CEVE (AB) block copolymers with narrow molecular weight distributions ([Mbar]w/[Mbar]n ~ 1.15) were obtained when αMeSt was polymerized first, followed by addition of CEVE to the resulting αMeSt living polymer solution. The reverse order of monomer addition, from CEVE to αMeSt, also led to a BA-type block copolymer. In the polymerization of a mixture of the two monomers, almost random copolymers were obtained. Living polymerizations of αMeSt were also induced with functional initiating systems, HCl-functionalized vinyl ether adducts (1b-1d)/SnBr4, to give end-function-alized poly(αMeSt)s with a methacrylate, an acetate, or a phthalimide terminal.  相似文献   

6.
A study of the copolymerization of α-pinene and styrene has been carried out at 10°C using anhydrous AlCl3 as the initiator. It is found that styrene forms copolymer with α-pinene at all mono-meric ratios. A copolymer of 2320–3080 molecular weight is obtained. The softening range of the copolymer is 82 to 85°C. The copolymers are of commercial value.  相似文献   

7.
The condensation of N-furfuryl- and N-tetrahydrofurfurylethylenediamines with hydrochloride salts of iminoesters of carboxylic acids gives 1,2-disubstituted 2-imidazolines containing furfuryl or tetrahydrofurfuryl groups at N1.For communication 2, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1312–1315, October, 1992.  相似文献   

8.
《Tetrahedron letters》1988,29(39):5001-5004
Whereas 1-benzyl-2-lithiomethyl-2-imidazoline undergoes reversible 1,2-addition to aldehydes and ketones, a derived phosphonate salt affords the condensation products, 2-(1-alkenyl)-2-imidazolines; the latter undergo conjugate addition with carbon nucleophiles.  相似文献   

9.
Aerosol particles composed of co-crystalline CO(2)·C(2)H(2) were generated in a bath gas cooling cell at cryogenic temperatures and investigated with infrared spectroscopy between 600 and 4000 cm(-1). Similar to results obtained for thin films of the co-crystal [T. E. Gough and T. E. Rowat, J. Chem. Phys. 109, 6809 (1998)], this phase was found to be metastable and decomposed into pure CO(2) and pure C(2)H(2). These decomposed aerosols were characterized through (i) a comparison to experimentally prepared aerosols of mixed CO(2) and C(2)H(2) of known architectures and (ii) the modeling of infrared spectra. A likely architecture after decomposition are C(2)H(2)-CO(2) core-shell particles with a disk-like shape. The co-crystalline CO(2)·C(2)H(2) aerosols prior to decomposition are modeled and analyzed in detail in the subsequent paper (Part II).  相似文献   

10.
Infrared absorption spectra of co-crystalline CO(2)·C(2)H(2) aerosol particles were modeled using a combination of two methods. Density functional theory was used to model several bulk CO(2)·C(2)H(2) co-crystal structures and to calculate their lattice energies and frequency-dependent dielectric tensors. This was necessary as there currently exists no crystallographic or refractive index data on co-crystalline CO(2)·C(2)H(2)due to its metastability. The discrete dipole approximation was then used to calculate infrared absorption spectra of different model particles using the dielectric tensors calculated using density functional theory. Results from these simulations were compared to the experimental spectrum of co-crystalline CO(2)·C(2)H(2) aerosol particles. The aerosol particles after the decomposition of the co-crystalline phase were studied in Part I.  相似文献   

11.
The acid halides of 1,2,4-oxadiazol-3-carbohydroxamic acids react with formaldehyde dimethylhydrazone to give the corresponding -oximohydrazones, which with hydrochloric acid rearrange to yield the dimethylhydrazone of 3-amino-4-formylfurazane. In the absence of an acid catalyst, the 5-trifluoromethyl derivative undergoes a rearrangement to give 1-dimethylamino-4-nitroso-3-trifluoroacetamidopyrazole.For Communication 4, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 976–978, July, 1991.  相似文献   

12.
Base treatment of the products of alkylation of-diketones by 2-chloromethylbenzimidazole under phase transfer catalysis (PTC) conditions causes loss of the acetyl group and formation of methylethyl- or ethylphenyl ketones.Rostov State University, Rostov-on Don 344090. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1067–1071, August, 1996. Original article submitted March 25, 1996.  相似文献   

13.
3,5-Disubstituted 2-isoxazolines containing furan fragments have been synthesized by 1,3-dipolar cycloaddition reactions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 449–452, April, 1991.  相似文献   

14.
In the interaction of 2--chlorobenzylidenehydrazino-4-ethoxycarbonylthiazole with triethylamine, a nitrilimine is formed as an intermediate that does not react with dipolarophiles, but rather undergoes intramolecular 1, 5-dipolar cyclization to form 3-phenyl-5-ethoxycarbonylthiazolo[2,3-c]-1,2,4-ttiazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, 253–255, February, 1994. Original article submitted November 30, 1993.  相似文献   

15.
16.
We have developed two synthesis routes for 4-amino derivatives of 6-nitro--carbolines: 1) consecutive conversion of 1,2-dimethyl-3-formyl-5-nitroindole to the 3-cyano derivative, condensation of the latter with DMF diethyl acetal, and cyclization of the enamine formed in this case with ammonia and benzylamine; 2) N-oxidation of 9-substituted 6-nitro--carbolines, transformation of N-oxides to the corresponding -carbolin-4-ones, from which the target compounds are obtained through the 4-chloro derivatives.For Communication 72, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 502–505, April, 1992.  相似文献   

17.
Blockcopolymersasidealcompatibilizershavefoundwideapplicationsinpolymerblends.Forblockcopolymerscontainingpolarblocks,itsadditiontoablendcontainingpolarcomponentsleadstothedecreaseininterfacialtensionbetweentheimmisciblephasesoftheblend,theincreaseinc…  相似文献   

18.
19.
《Tetrahedron letters》1987,28(40):4669-4672
(+)-(R) [or (-)-(S)] dimethyl α-methylsuccinates, obtained by the enantioselective hydrolysis of the racemic diester by porcine pancreatic lipase, undergo acyloin cyclization followed by stereoselective ring contraction to provide 1-alkenylcyclopropanols with high enantiomeric excesses.  相似文献   

20.
Sixteen title compounds were synthesized, twelve of which are new ones. Their structures were determined by 1H NMR, IR and MS, the refractive indices or melting points were measured. Odors of all the title compounds were evaluated and the structure-odor relationship was briefly discussed.  相似文献   

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