首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Preparations of polymers with bis(dimethylglyoximato)cobalt (cobaloxime) were investigated. 4-Vinylpyridine was reacted with α-cyanoethylaquocobaloxime to produce α-cyanoethyl-4-vinylpyridinatocobaloxime (I) in 72% yield. It did not, however, polymerize by the use of azobisisobutyronitrile (AIBN) as an initiator. Polymers containing α-cyanoethylcobaloxime were obtained by reactions of polymers with α-cyanoethylaquocobaloxime (II). Poly(9-O-methacryloylquinine) (III), poly(O-methacryloyl-N-methyl-L -ephedrine) (IV), poly[Nα-(o-vinylbenzyl)-L -histidine] (V), and poly(4-vinylpyridine) (VI) were prepared and used in these reactions. Polymers V and VI were reacted with II to give polymers X, XI, XII, and XIII containing α-cyanoethylcobaloxime.  相似文献   

2.
2′-Deoxy-ψ-isocytidine (VIIβ), a 2′-deoxy analog of antileukemic ψ-isocytidine and also a C-nucleoside analog of deoxycytidine, was synthesized from ψ-uridine by making use of the newly discovered pyrimidine to pyrimidine transformation reaction [J. Chem. Soc., 14, 537 (1977)]. 2′-Deoxy-ψ-uridine (IIβ) and 2′-deoxy-l-methyl-ψ-uridine (V), both C-nucleoside analogs of deoxyuridine and thymidine, were also synthesized. ψ-Uridine was converted into the 2′-chloro analogs (I) which was reduced with tributyltin hydride to give an α,β-mixture of 2′-deoxy-ψ-uridines. The β-isomer (11β was trimethylsilylated and the product (III) treated with methyl iodide to afford the 1-methyl derivative (IV). After hydrolytic removal of the trimethylsilyl groups from IV, the thymidine analog (V) was obtained in good yield. A crude mixture of II was converted in good yield into an α,β-mixture of 1,3-dimethyl-2 -deoxy-ψ-uridines (VI) by treatment with DMF dimethyl acetal in DMF. Treatment of the β-isomer (VIβ) with guanidine, however, gave the α,β-mixture of 2 -deoxy-ψ-isocytidines (VII). The pure β-isomer (VIIβ) was obtained by thick layer chromatography. The pure α-isomer (VIIα) was obtained when VIα was treated with guanidine. 2 -Deoxy-ψ-isocytidine (VIIβ) and 2 -deoxy-l-methyl-ψ-uridine (V) exhibited inhibitory activity against P815 cells (ID5 0 1.2 μg./ml. and 4.9 μg./ml., respectively) and the thymidine analog V was found to be active against Streptococcus faecium var. duran. J. Heterocyclic Chem., 14, 1119 (1977)  相似文献   

3.
Summary: By the Suzuki coupling reaction of 9,9-dioctyl-2,7-bis(1,3,2-dioxaborinan-2-yl)fluorene ( I ) and 3,5-di-tert-butylphenyl 2,5-dibromobenzenesulfonate ( II ) the alternating poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[2-(3,5-di-tert-butyl-phenoxysulfonyl)-1,4-phenylene]} ( III ) was synthesized. Alkaline hydrolysis of III gave a conjugated polyelectrolyte carrying sulfonic acid groups ( IV ). Monomers 2,5-dibromo-3-[2-(pyren-1-yl)vinyl]thiophene and 2,5-dibromo-3-[2-(quinolin-4-yl)vinyl)thiophene were prepared and copolymerized with I to afford poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[3-(2-(pyren-1-yl)vinyl)thiophen-2,5-diyl]} ( V ) and poly{[9,9-dioctylfluoren-2,7-diyl]-alt-[3-(2-(quinolin-4-yl)-vinyl)thiophen-2,5-diyl] ( VI ), respectively. Conjugated backbone of V contains the conjugated pyrene unit in the side chain. Similarly the side chain of VI contains the conjugated quinoline structure unit which can be for instance protonated. By the Suzuki polycondensation reaction of I and of the prepared methyl 3-(2,7-dibromocarbazole-9-yl)propionate ( VII ) the new poly{[9,9-dioctylfluorene-2,7-diyl]-alt-[9-(2-methoxycarbonylethyl)carbazole-2,7-diyl]} ( VIII ) was synthesized and characterized.  相似文献   

4.
Oxidation products of ajmaline (I), two of its diastereomers isoajmaline (II) sandwicine (III) and their corresponding diacetyl derivatives namely diacetyl ajmaline (IV), diacetyl isoajmaline (V) and diacetyl sandwicine (VI) has been synthesized by their direct reaction with H2 O 2 and characterised by spectroscopic studies.  相似文献   

5.
Oximidobenzotetronic acid is recommended for the separation and gravimetric determination of palladium and cobalt An ethanolic solution of the reagent quantitatively precipitates palladium(II) from solutions which are 0.75 N in acid up to pH 5.1, the complex is weighed as Pd(C9H5NO4)2. Cobalt(II) can be determined in the filtrate after the precipitation of palladium. With 0.5 N acid solutions, no interference was found from Pt(IV), Ir(IV), Rh(III), Ru(III), Os(IV), Au(III), Ag(I), Cu(II), Fe(III), Ni(II), Hg(II). Pb(II), Bi(III), Cd(II), As(V), Se(VI), Te(IV), Mo(VI), Sb(III), Al(III), Cr(III), Zn(II), Ti(IV), Zr(IV). acetate, oxalate, citrate, tartrate, phosphate and fluoride.  相似文献   

6.
In the polymerization of α-methylstyrene (α-MeSt) in dichloromethane in the temperature interval between ?60 and ?20°C the polymer yield decreased with increasing temperature depending on the initiating system used (I-IV) in the series II > I > IV > III, where I was a freshly prepared solution of 2,5-dichloro-2,5-dimethylhexane (DDH) with BCl3 in dichloromethane, was the same solution as in the preceding case, but stored at room temperature one month and then used, III was a freshly prepared BCl3 solution in dichloromethane, and IV was the initiation system “H2O”/BCl3. The polymer samples synthesized at ≤ ?30°C had a bimodal molecular weight distribution (MWD), which was attributed to the different participation of ionic pairs and free ions in the propagation reaction. The stereoregularity of the polymer observed (ca. 85% syndiotactic and ca. 15% heterotactic triads) determined from the 1H-NMR spectra was not affected by the difference in the initiation system. MWD of the polymer samples was investigated by the GPC method  相似文献   

7.
A new polystyrene-divinylbenzene resin containing 1-(2-thiazolylazo)-2-naphthol (TAN) functional group was synthesized and its sorption behavior for 19 metal ions including Zr(IV), Hf(IV) and U(VI) was investigated by batch and column experiments. The chelating resin showed a high sorption affinity for Zr(IV) and Hf(IV) at pH 2. Some parameters affecting the sorption of the metal ions are detailed. The breakthrough and overall capacities were measured under optimized conditions. The overall capacities of Zr(IV) and Hf(IV) that were higher than those of the other metal ions were 0.92 and 0.87 mmol/g, respectively. The elution order of metal ions at pH 4 was evaluated as: Zr(IV)>Hf(IV)>Th(IV)>V(V)>Nb(V)>Cu(II)>U(VI)>Ta(V)>Mo(VI)>Cr(III)>Sn(IV)>W(VI). Quantitative recovery of most metal ions except Zr(IV) was achieved using 2 M HNO3. Desorption and recovery of Zr(IV) was successfully performed with 2 M HClO4 and 2 M HCl.  相似文献   

8.
Poly(divinylbenzene) [poly(DVB)] derivatives having hydroxyl terminals and/or pendants were synthesized by chemical modifications (hydration and hydroxylation) of unsaturated linear poly(DVB) ( I ), which was prepared by the polymerization of DVB catalyzed by acetyl perchlorate. Hydroboration of both terminal and in-chain carbon–carbon double bonds in I with BH3.THF complex yielded a fully hydrated poly(DVB) II , in which hydrophilic and hydrophobic groups are placed alternately. Selective hydroboration of the vinyl endgroups in I with 9-borabicyclo[3.3.1]nonane led to an α,ω-dihydroxy-poly(DVB) ( III ). Reaction of I with m-chloroperbenzoic acid gave fully epoxidated poly(DVB) IV , which was subsequently hydrated to yield polymer V consisting of glycol repeat units and terminals. The physical properties and reactions (chain extension and crosslinking) of these polymers were also studied.  相似文献   

9.
Metallation of 1,1-dibutyl-1-stannacyclohexadiene-2,5 (I) with lithiumamides yield the lithium compound II, from which the trimethylsilyl-, germyl-, -stannyl- and the bromoethyl-substituted stannacyclohexadienes III, IV, V and VI are obtained. The bis(trimethylsilyl- and -germyl) substituted stannacyclohexadienes VIII and X have been synthesized starting from III and IV, respectively. Arsabenzene (XII) is formed in good yields by treating arsenic trichloride with III, IV and V. 4-Trimethylsilyl-1-arsabenzene (XIII), 4-trimethylgermyl1-arsabenzene (XIV) and 4-(2-chloroethyl)-1-arsabenzene (XV) can be prepared by treating VIII, X and VI respectively with arsenic trichloride, 1H NMR, IR, UV and mass spectral data of the new compounds are described.  相似文献   

10.
Summary Use of the ring oven in separation and identification of mixtures of less familiar metal ions has been described. Separation of metal ions from the following mixtures has successfully been carried out: 1. UO2(II) and Th(IV), 2. Th(IV) and Ce(IV), 3. Pd(II) and Au(III), 4. Pt(IV) and Au(III), 5. Ce(III) and Ce(IV), 6. UO2(II), Th(IV) and Ti(IV), 7. Th(IV), Ti(IV) and Ce(IV), 8. Th(IV), Ce(IV) and Zr(IV), 9. Ti(IV), V(V) and Zr(IV), 10. Mo(VI), V(V) and W(VI) and 11. Be(II), Al(III) and Mg(II). In the case of binary mixtures, the separation was in the form of a central spot and a concentric ring; in ternary mixtures the metals were precipitated in a central spot and two concentric rings.
Zusammenfassung Zur Trennung und Identifizierung folgender Gemische seltenerer Metallionen wurde der Ringofen mit Erfolg verwendet: 1. UO2(II) und Th(IV), 2. Th(IV) und Ce(IV), 3. Pd(II) und Au(III), 4. Pt(IV) und Au(III), 5. Ce(III) und Ce(IV), 6. UO2(II), Th(IV) und Ti(IV), 7. Th(IV), Ti(IV) und Ce(IV). 8. Th(IV), Ce(IV) und Zr(IV), 9. Ti(IV), V(V) und Zr(IV), 10. Mo(VI), V(V) und W(VI) und 11. Be(II), Al(III) und Mg(II). Bei binären Gemischen erfolgt die Trennung in einen zentralen Fleck und einen Ring, bei ternären Mischungen in einen Fleck und zwei konzentrische Ringe.

Résumé On a décrit l'utilisation du four annulaire pour la séparation et l'identification de mélanges d'ions métalliques moins courants. On a effectué la séparation des ions métalliques à partir des mélanges suivants: 1. UO2(II) et Th(IV), 2. Th(IV) et Ce(IV), 3. Pd(II) et Au(III), 4. Pt(IV) et Au(III), 5. Ce(III) et Ce(IV), 6. UO2(II), Th(IV) et Ti(IV), 7. Th(IV), Ti(IV) et Ce(IV), 8. Th(IV), Ce(IV) et Zr(IV), 9. Ti(IV), V(V) et Zr(IV), 10. Mo(VI), V(V) et W(VI) et 11. Be(II), Al(III) et Mg(II). Dans le cas des mélanges binaires, la séparation se présentait sous forme d'une tache centrale et d'un anneau concentrique; chez les mélanges ternaires, les métaux étaient précipités en une tache centrale et deux anneaux concentriques.
  相似文献   

11.
Tricyclic tetrahydro-1,3-oxazines-5,6-trimethylenetetrahydro-1,3-oxazine-4-spirocyclopentanes IV, V, and VII — were synthesized on the basis of 2-(1-isothiocyanatocyclopentyl)cyclopentanone (I). The reductive cyclization of the latter by the action of sodium borohydride leads to oxazinethione V; the acidic hydrolysis of I with subsequent reduction of amino ketone hydrochloride II with sodium borohydride and the reaction of isothiocyanato ketone I with lithium aluminum hydride make it possible to obtain 1,3-amino alcohols III and VI, respectively, which are converted to tetrahydro-1,3-oxazines IV and VII by cyclization with formaldehyde. Pyrimidinethione VIII was synthesized from isothiocyanato ketone I and methylamine. Compounds III–VII are mixtures of stereoisomers with predominance of the cis isomer.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1256–1259, September, 1990.  相似文献   

12.
Spiroorthoesters (SOEs), cis‐2,3‐tetramethylene‐1,4,6‐trioxaspiro[4,5]decane ( I ) and cis‐2,3‐tetramethylene‐1,4,6‐trioxaspiro[4,6]undecane ( II ), with different cyclic ether ring sizes were synthesized, and their stereostructure and steric energy were determined. With steric‐hindrance‐sensitized 9‐phenyl‐9,10‐dihydro‐anthracen‐10‐ylium cation as an initiator, I and II underwent regiospecific polymerization to yield trans form of stereoregular poly(ether esters)—poly(trans‐2‐oxycyclohexyl pentanoate) (? [trans‐2‐OCHP]n? ) ( III ) and poly(trans‐2‐oxycyclohexyl hexanoate) (? [trans‐2‐OCHH]n? ) ( V ), respectively. With SnCl4 as another initiator, I and II underwent regiospecific polymerization through different mechanisms to afford cis form poly(cis‐2‐oxycyclohexyl pentanoate) (? [cis‐2‐OCHP]n? ) ( IV ) and trans form (? [trans‐2‐OCHH]n? ) ( VI ) stereoregular poly(ether esters). The polymerization mechanisms of SOEs proceeded in the regiospecific manner were determined by the relationship among the sterostructures of SOEs and its subsequently formed polymers, the steric energy of monomers, and the free energy difference in the transition state of reaction. Owing to the conversion of cis substitution at C‐2 and C‐3 in I or II to the trans form during polymerization, polymers III , V , and VI exhibited a higher volume of expansion during polymerization than IV , which showed high volume shrinkage. Group contributions of divalent trans‐ and cis‐1.2‐cyclohexyl groups were derived and confirmed by measuring the densities of the corresponding stereoregular polymers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

13.
Phase equilibria in quasi-binary sections of the Tl-Sn-S system: (I) Tl4SnS4-SnS, (II) Tl2SnS3-SnS, (III) S-Tl4SnS4, (IV) S-Tl2SnS3, (V) Tl-SnS, and (VI) Tl2S-SnS were studied by differential thermal analysis and X-ray powder diffraction. It was found that systems I and II are characterized by the eutectic type of interaction, the phase diagrams of systems III and IV are of the eutectic type with a degenerate eutectic at the sulfur melting point, and the phase diagram of system V is of the fourth type according to Roozeboom. Phase equilibria in system VI were specified.  相似文献   

14.
Three bis(dimethylamino)silane monomers have been polymerized with 1,1'-bis-(hydroxymethyl)ferrocene to give ferrocene-containing polyoxysilanes I and II. They were bis(dimethylamino)dimethylsilane (III), bis(dimethylamino)diphenylsilane (IV), and 1,4-bis(N,N-dimethylaminodimethylsilyl)benzene (V). Mixing of the diol and III or IV at O°C followed by heating resulted in polymerization to higher molecular weights than when the monomers were initially mixed at higher temperatures. At higher temperatures the formation of monomeric cyclic products seriously competed with polymerization, and the five atom bridged derivative, 3-sila-2,4-dioxa-3,3diphenyl[5]ferrocenophane (VI) was isolated in good yield. The use of silane V, where cyclization is not expected to compete, led to higher polymer yields and molecular weights. The polymers were low melting and I (R = C6H5) could be cast into films and weak fibers were drawn from its melt. The polymers were sensitive to hydrolytic decomposition; those containing Si-CH3 linkages were completely hydrolyzed in refluxing THF-H2O (10:1) in 1 hr. The polymers were characterized by viscosity studies, gel-permeation chromatography, and infrared and NMR spectroscopy.  相似文献   

15.
Vanadium(III) obtained by dithionite reduction of vanadium(V) can be extracted as its ferron complex with tribenzylamine in chloroform from 0.05 M sulphuric acid. Vanadium (0–5 μg ml-1) is determined spectrophotometrically at 430 nm with a sensitivity of 0.0028 μg V cm-2. Al(III), Co(II), Ni(II), Fe(II, III), Hg(II), Si(IV), Be(II), Mg(II), Ca(II), Sr(II), Ba(II), Cr(VI, III), W(VI), Zn(II), U(VI), Mn(II). Pb(II), Cu(II), Cd(II) and Th(IV) do not interfere; only Mo(VI), Ti(IV), Zr(IV). Bi(V) and Sn(II) interfere. A single determination takes only 7 min. The extracted complex is VIII (R-3H.TBA)3 where R = C9H4O4NSI. The method is satisfactory for the determination of vanadium in steels, alum and other samples without preliminary separations.  相似文献   

16.
T. Shimizu  S. Abe 《Chromatographia》1986,21(12):708-710
Summary The thin-layer chromatographic behavior of 49 inorganic ions on polyethyleneimine (PEI) cellulose has been investigated in hydrochloric acid media (0.01–1.0 mol dm−3). The sorption on the cellulose decreases with increasing acid concentration for most of the ions, but As(III), Ti(IV) and Te(VI) do not exhibit any Rf variation with the acid concentration. The Rf spectra of TI(I), Cd(II), Pb(II) and Zn(II) have a maximum. Ag(I), Bi(III), Nb(V), Ta(V), Mo(VI) and W(VI) are retained tightly on the layer, due to either insoluble salt formation or extensive hydrolysis. The extremely low Rf values of Hg(II), Pd(II), Au(III), Ru(III) and Pt(IV) are accounted for by stability of their chlorocomplexes. Re(VII) distributes chromatographically, having moderate Rf values between 0.3 and 0.6, so that the selective separation of Re(VII) from the other ions is feasible.  相似文献   

17.
Synthesis of perfluorophenylcyclopropane (I) and I-chloro-I-pentafluorophenyltetrafluorocyclopropane (II) is described and their pyrolysis at 620°C is studied. Pyrolysis of compounds (I) and (II) is shown to give perfluorostyrene (III) and α - chloroheptafluorostyrene (IV) as the main products, together with a small amount of perfluoroindan (V) and I-chlorononafluoroindan (VI), respectively. Styrene (III) was obtained by bromofluorination of styrene (IV) and subsequent dehalogenation of the resultant α - chloro- β - bromooctafluoroethylbenzene (VII).  相似文献   

18.
Direct and indirect potentiometric, bipotentiometric and biamperometric titrations with a standard iron(II) solution are described for some inorganic compounds in alkaline media containing hexitols (mannitol, dulcitol and sorbitol). The optimal conditions for titrations based on the Cr(VI) → Cr(III), Mn(IV) → Mn(III) → Mn(II), V(V) → V(IV), Co(III) → Co(II) and U(VI) → U(IV) systems are discussed. Of the hexitols studied, sorbitol has the greatest effect on the value of the redox potential of the Fe(III)/Fe(II) system; the Ef° value is about —1.10 V vs. SCE.  相似文献   

19.
Summary Thin-layer chromatographic behavior of 58 inorganic ions on polyethyleneimine (PEI) cellulose has been systematically surveyed in hydrochloric acid — ammonium thiocyanate media. In this media most of the ions distribute chromatographically on the layer. Ag(I), Hg(II), Pd(II), Au(III), Bi(III), Ru(III), Pt(IV), Nb(V), Ta(V), Mo(VI), and W(VI) are strongly retained, while alkali earths(II), Mg(II), As(III), Ti(IV), and Te(VI) are not absorbed to any great extent in this system. An interesting correlation was found between the Rf values on PEI-cellulose in the thiocyanate media and the paramagnetic moment of the rare earths(III). An oddeven fluctuation against the atomic number is also found for the heavy rare earths(III). Chromatographic separation of many inorganic ions of analytical interest is demonstrated in this system.  相似文献   

20.
Aryl aldehydes I reacted with α-tetralone to give the corresponding 2-arylidene-1-tetralone II. Condensation of the latter chalcones with hydrazine, methylhydrazine and phenylhydrazine produced the corresponding benzo[g]indazoles III, V and VI respectively. Acetylation of the 2H-benz[g]indazole derivatives III gave the corresponding 2-acetylated compounds IV. The structure of all products was elucidated by chemical and spectroscopic methods.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号