Copolymerization of N-Phenylmaleimide with Cyclohexene

MalebodeanditSderivatvesarewell-bowntopolyInrizetogivethermallystablepolyTnersandthecopolymeriZationwithvariousvinylmonomershasbeenexaminedtohaProvethethermalpropeniesofthepolymers[';-'].HoweverlessworkhasbeendoneonthecopolyInerizationofN-phenylmaletride(PHMI)withcyclohexene(CH).Inthisletter,wesynthesizedanewcopolymerfromthepolymerizahonofPHMIwithCH.ThemonomerPHMIwaspreparedfrommaleicanhydrideandedlineaccordingtoT.OkadaI41.2,2'-Azobisisobutyronitrile(AIBN)wasrecrystallizedtWicefro…     

O-phosphorylation of Oligopeptides with Phosphoramidite

Phosphoproteinsplayimportantrolesinbiologicalsignallingcascades,bywhichchemicalsignalsarepassedacrossthecellmembraneandfurthertothecellnucleusl.Forthestudythisprocess,structurallywell-definedpeptidescontainingthecharacteristiclinkageregionofthepeptidebackbonewiththephosphoricacidestercanusedwithmanyadvantages.Ingeneral,estersofoligopeptideswerephosphorylatedwithphosphorylchlorideorwithdialkylordiarylphosphorochloridates'.Butaminogroupsinoligopeptidesshouldbeprotectedwhenhydroxylgroupswerephosp…     

Cyclopropanation of Diazoacetate with Olefins

ＣｙｃｌｏｐｒｏｐａｎａｔｉｏｎｏｆＤｉａｚｏａｃｅｔａｔｅｗｉｔｈＯｌｅｆｉｎｓＣｙｃｌｏｐｒｏｐａｎａｔｉｏｎｏｆＤｉａｚｏａｃｅｔａｔｅｗｉｔｈＯｌｅｆｉｎｓ￥ＺｈｅｎｇＮｉｎｇＬＩ；ＨｕｉＬｉｎＣＨＥＮ（ＤａｌｉａｎＩｎｓｔｉｔｕｔｅｏｆＣｈ...     

On study of chemoselectivity of reaction of trialkylalanes with alkenes, catalyzed with Zr π-complexes

The influence of the organoaluminium compound nature, Zr π-ligand environment, solvent type and reagent ratio on the chemoselectivity of reactions of trialkylalanes (AlMe₃, AlEt₃) with alkenes, catalyzed with L₂ZrCl₂ [L = Cp, Cp′ (Cp′-η⁵-C₅H₄CH₃), Cp^∗ (Cp^∗-η⁵-C₅(CH₃)₅), Ind (indenyl), Flu (fluorenyl)] has been studied. It is shown that in the case of AlMe₃, the hydro- and carboalumination products, and alkene dimers are formed. The catalytic reaction of AlEt₃ with the olefins yields aluminacyclopentanes altogether with the hydro- and carboalumination products, and the dimers. A probable reaction mechanism has been proposed.     

Mechanism of Dealumination of NaY Zeolite with Oxalic Acid

RemovalofalundnumfromNaYzeolitewithacidisanimportantprocessinthemodificationofzeolite.ItisdifficulttoremovealundnumfromNaYzeolitedirectlywithacidwhilekeepinghighcrystallinity.Intheworkreportedhere,alundnumisremoveddirectlyfromNaYwithoxalicacidandthemodifiedzeolitekeepshighcrystallinity.Reactionconditions:CSBlreflux,acidaddedin3ondn,allowedtoreactfor3OAnn.CSB2reflux,acidaddedrapidly,allowedtoreactfor3Owhn.CS2525-C,acidaddedraPidly,allowedtoreactfor3Omin.CSA25"C,acidaddedin3omin,a1lowe…     

Condensation of p-Benzoquinone with Anilides of β-Aminocrotonic Acid

Benzofuranone derivatives have been synthesized by the condensation of p-benzoquinone with anilides of -aminocrotonic acids under the conditions of the Nenitzescu reaction.     

Production of Superoxide Ion with Carbon Gas-Diffusion-Electrode And Reaction of Superoxide Ion with Aromatic Halide

Superoxide ion O~-_2 is prepared in aprotic media by carbon gas-diffusion-electrode for the first time. The experimental results indicate that this electrode is superior to carbon plane-electrode in the reaction of O~-_2 with p-bromonitrobenzene. When the gas-diffussion-electrode is used, the yield of the product nitrophenol increases by 20%, and the selectivity of the reaction is nearly doubled as compared with the plane-electrode.     

Reactions of α-halonitrosoalkanes with resorcinol

-Halonitrosoalkanes react with resorcinol as nitrosylating agents to form 3-hydroxy-N-(2,4-dihydroxyphenyl)-1,4-quinone imine.Translated fromIzvestiya Akademioi Nauk. Seriya Khimicheskaya, No. 3, pp.773–774, March, 1996.     

The reaction of Tanshinones with Amines

The reaction of cryptotanshinone and tanshinone IIA with several biogenic amine metabolites involved in the pathogenic pathways of HE were investigated and eight 1,2,3,4-tetrahydrophenanthrene derivatives,2-6 and 8-10,were obtained.The probable mechanism on reaction was discussed.     

Copolymerization of Isobutylene with α-Pinene

The copolymerization of isobutylene with α-pinene has been investigated by using EtA1Cb in ethyl chloride diluent at ca. -105°C. The copolymerizations proceeded readily and gave random copolymers of reasonably high molecular weights. Copolymer homogeneity, composition and structure was investigated by GPC, solubility behavior, PMR (60 and 300 MHz), CMR, reactivity ratio determination, and vulcanization behavior.     

Reactions of α-nitroacrylates with thiophenols

Reactions of α-nitroacrylates with aromatic thiols like 4-methyl- and 4-chlorothiophenols afford a series of new 3-arylsulfanyl-2-nitropropanoates. The latter were isolated as diastereomerically pure substances or mixtures of two diastereomers. Structures of the obtained S-adducts were confirmed by IR, ¹H and ¹³C-{¹H} NMR spectroscopy using HMQC and HMBC experiments.     

Reaction ofβ-arylacryloyloxiranes with phenylhydrazine

The reaction of -arylacryloyloxiranes with phenythydrazine under the conditions of acid catalysis leads to 3 arylvinyl-I-phenylpyrazoles and 2-hydroxymethyl-5-aryl-1,4-pentadien-3-one phenythydrazones.Belorussian State Technological University. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3 pp. 324–327, March, 1996. Original article submitted June 26, 1995.     

Reaction of ω-Vinyloxyalkylamines with Isatin

3-(-Vinyloxyalkylimino)-2,3-dihydroindol-2-ones and 3-(vinyloxyphenylimino)-2,3-dihydroindol-2-ones were synthesized in 34-93% yield by reactions of -aminoalkyl and aminophenyl vinyl ethers with isatin.     

Mono-Allylation of Gem-Diacetates with Allylsamarium Bromide

Our group have explored the reaction of allylsamarium bromide with a variety of substrates, such as N-(2-aminoalkyl)benzotriazoles1, imines2, nitriles3, diorgano diselenides4, disulfides5, isocyanates6 and nitroalkenes7. Here we wish to report the monoallylation of gem-diacetates with allylsamarium bromide. Gem-diacetates are stable in neutral and basic media, thus they are frequently used to protect aldehydes8. However, the presence of two leaving groups at the same carbon may make carbon …     

Synthesis of Indomethacin Conjugates with D-Glucosamine

Two series of indomethacin conjugates with D-glucosamine were prepared with the objectives of reducing ulcerogenic potency, increasing the bioavailability of indomethacin and exerting the coordinative effects on osteoarthritis. The structures of the conjugates were identified by ^1H NMR and ^13C NMR. The ester conjugates inhibited edema as potent as indomethacin.     

Reactions of aminals of conjugated ω-dimethylaminoaldehydes with coumarin derivatives

The reactions of aminals of conjugated -dimethylaminoaldehydes with various derivatives of 4-methyl- or 3-acetyl coumarins produce -dimethylaminopolyenones containing coumarin fragments. Unlike the starting coumarins, these polyenones practically do not fluoresce. Dialkyl-substituted coumarins with hydroxyl groups in positions 5 or 7 react with -dimethylaminoacrolein aminal to give salts consisting of 1 mole of doubly charged dimethylaminopropenylidenedimethylammonium cations and 2 moles of phenoxide ions (derived from the starting coumarins). The structure and the properties of the salts in solutions have been studied by absorption and fluorescence spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 537–543, March, 1995.The authors are grateful to I. V. Komlev for providing coumarins3 and4.