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1.
用pH电位法研究了1-乙酰胺基丙叉-1,1-二膦酸(S-186)和1-丙酰胺基乙叉-1,1-二膦酸(S-106)与碱土金属的螯合作用(30±O.1℃).当金属离子与配体的摩尔浓度比为10∶1、1∶1和1∶2时,在水溶液中形成了MHL、ML、ML_2和M_2L等几种类型的配合物.分别测定了它们的稳定常数,其中S-186配合物稍高于S-106,说明配合物稳定性与螯合剂的碱度有平行关系.值得注意的是,这两种螯合剂与Sr~(2 )形成的双核配合物的稳定性均较其它碱土金属离子的为高.  相似文献   

2.
Cycloheptatriene reacts with acrylic esters, in the presence of catalytic amounts of tricarbonyl-triphenylphosphine-nickel, to yield a mixture of α-cycloheptatrienyl-propionic acid esters ( 2a ) substituted in various positions. Methacrylic acid ester yields likewise α-cycloheptatrienyl-isobutyric acid ester ( 3a ). Both types of ester mixtures undergo thermal isomerizations by 1,5-hydrogen shifts to give mixtures which contain predominantly the (C-1)-substituted cycloheptatrienyl-carboxylic acid esters ( 2a , 3a ). Pure α-(1-cycloheptatrienyl) derivatives can be prepared from 2a and 3a . A detailed NMR. study of the ester mixtures before and after thermal isomerization shows the proportions of the various isomers in the mixture. The mechanism of the formation of 2a and 3a is explained in terms of a catalysed ene-reaction of the primary formed 7-substituted cycloheptatriene derivatives with subsequent consecutive 1,5-hydrogen shifts.  相似文献   

3.
1-Amino-2-methylenecyclopropane-1-carboxylic acid (2-methylene-ACC) is an irreversible inhibitor for a bacterial enzyme, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, which catalyzes the conversion of ACC to alpha-ketobutyrate and ammonia. The inactivation has been proposed to proceed with the ring scission induced by an addition of an enzyme nucleophile, resulting in the formation of a reactive turnover product that then traps an active-site residue. To gain further insight into this unique enzymatic reaction, the tritiated 2-methylene-ACC was prepared and incubated with ACC deaminase to locate and identify the entrapped amino acid residue. The synthesis of this radiolabeled compound and the results of its incubation with ACC deaminase are reported in this paper.  相似文献   

4.
The oxidative cyclization in boiling nitrobenzene of 4,6-diaminodiphenylamine-2-carboxylic acid gave 3-aminophenazine-1-carboxylic acid. 4,6-Diaminodiphenylamine-3-carboxylic acid underwent decarboxylation, but the methyl ester gave methyl 3-aminophenazine-2-carboxylate from which the acid was obtained. 2,4-Diaminodiphenylamine-3′-carboxylic acid gave a mixture of 7-aminophenazine-2- and 8-aminophenazine-1-carboxylic acids from which the pure acids were separated and oriented. 8-Aminophenazine-1-carboxylic acid, together with some 1,8-diamino-acridone, was also obtained from 3′,6-diaminodiphenylamine-2-carboxylic acid.  相似文献   

5.
Copolymers containing N-1-ethylitaconamic acid, N-1-propyl-itaconamic acid, N-1-butylitaconamic acid, N-1-hexylitaconamic acid, N-1-octylitaconamic acid and N-1-decylitaconamic acid with styrene of different comonomer compositions were synthesized and characterized. Copolymer composition was determined by elemental analysis following the nitrogen content in the resulting copolymers. Monomer reactivity ratios r1 and r2 of the different copolymers were estimated using straight line intersection procedures such as Fineman-Ross (F-R) and Kelen-Tüdos (K-T) and by a nonlinear one, according to the reactivity ratios error-in-variables model (RREVM). Good agreement between the different procedures for r1 and r2 determination was found. Differences in the reactivity of N-1-alkylitaconamic acids (NAIA) relative to styrene were found i.e., ethyl and propyl derivative are less reactive with itself than butyl, hexyl, octyl, and decyl derivatives with itself. Copolymers with some tendency toward small block formation are found.  相似文献   

6.
1-Halo-2-arylthioalk-1-enes, the anti-Markovnikov adducts of 1,2-halosulfenylation of terminal alkynes containing propargyl hydrogen atoms, were found to transform into a mixture of E - and Z -isomers of 1-halo-2-arylthioalk-2-enes under acid catalysis conditions. A plausible mechanism of rearrangement is proposed. The Markovnikov adducts 2-halo-1-arylthioalk-1-enes were partially converted into their cis -form under similar conditions. The halosulfenylation products of 1-phenylpent-1-yne did not show the signs of double-bond migration in the presence of an acid; only partial isomerization of the E - to the Z -isomers took place.  相似文献   

7.
1-Aminoalkane-1,1-diphosphonic acids 1 , 2 or 3 are formed in the reaction of carboxylic acid amide dihalides or carboxylic acid amide hydrohalogenides with phosphorous acid. Phosphorus trihalides plus water may be used in lieu of phosphorous acid in the reaction with carboxylic acid amides. With formamide either aminomethanediphosphonic acid ( 1a ) or 2-oxo-2-hydroxy-5-amino-1,4,2-oxazaphospholidine-3-phosphonic acid ( 5 ) are obtained depending on the reaction conditions.  相似文献   

8.
The reaction of 1-phenylthio-1-trimethylsilylethene (1) with various electrophiles, in particular acid chlorides, has been investigated.  相似文献   

9.
Bromination of 3,4,4-trichlorobut-3-enoic acid in boiling carbon tetrachloride led to the formation of 2-bromo-3,4,4-trichlorobut-3-enoic acid as a result of replacement of hydrogen in the CH2 group. The reaction at 40°C involved the double C=C bond to give 3,4-dibromo-3,4,4-trichlorobutanoic acid. The brominated acids were converted into the corresponding chlorides which were used to acylate benzene, toluene, and bromobenzene according to Friedel-Crafts. The acylation was not selective, and only the reaction of 3,4-dibromo-3,4,4-trichlorobutanoyl chloride with benzene gave 3,4-dibromo-3,4,4-trichloro-1-phenylbutan-1-one as the only product. 1-Aryl-2-bromo-3,4,4-trichlorobut-3-en-1-ones were synthesized by bromination of the corresponding 1-aryl-3,4,4-trichlorobut-3-en-1-ones which were prepared previously by Friedel-Crafts acylation of substituted benzenes with 3,4,4-trichlorobut-3-enoyl chloride.  相似文献   

10.
Reactions with alcohols and base replaced the vinylic fluorine of 1-trifluoromethylnonafluorocyclohex-1-ene(I) by methoxy and ethoxy groups. Fluorination with cobaltic fluoride gave, from the former, a number of saturated polyfluoro-ethers. Oxidation of the alkoxy-cycloalkenes gave hexafluoroglutaric acid. Cycloalkene I gave which ammonia an imino-enamine, which was hydrolysed by dilute acid to a keto-enamine. I was defluorinated by heated iron to octafluorotoluene.  相似文献   

11.
田红玉  孙宝国 《化学通报》2004,67(12):934-937
介绍了一种简单的制备(1R,3S)-3-氨基1环己烷羧酸的方法。以环己烷-1,3-二羧酸的顺反混合物为原料。经过关环得顺式的酸酐,然后酯化,在脂肪酶AY-30的作用下进行去对称性水解。得光学活性的环己烷-1,3-二羧酸的单乙酯产物,经过改进的Curtis重排反应后,羧酸基团转变为氨基。然后经过酯水解、去保护基团,得到光学纯的(1R,3S)-3-氨基-1-环己烷羧酸。  相似文献   

12.
邻苯二甲酸酐与丙二酸反应合成邻乙酰基苯甲酸(1);1经酰氯化反应得邻乙酰基苯甲酰氯(2);2与伯胺反应合成了3个1-羟基-1-甲基-3-氧-异吲哚化合物,总收率65.0%~76.8%,其结构经1H NMR, 13C NMR, IR和MS表征.  相似文献   

13.
Xuxiang Zhu  Ping Gan 《合成通讯》2013,43(17):3159-3162
A novel synthetic route of 1-aminocyclopropane-1-carboxylic acid (ACC) has been built via cyclopropanedicarboxylic acid monohydrazide III in moderation to good yield.  相似文献   

14.
Lithium aluminum hydride reduction of 5-substituted or unsubstituted ethyl or methyl 1-aryl-1H-pyrazole-4-carboxylates gave, generally in excellent yields, 5-substituted or unsubstituted 1-aryl-1H-pyrazole-4-methanols which afforded the corresponding 1-aryl-4-(bromomethyl)-1H-pyrazoles with hydrobromic acid in acetic acid solution. These crude intermediates gave by reaction with potassium cyanide in dimethylsulfoxide solution 1-aryl-1H-pyrazole-4-acetonitriles only in the case of 5-unsubstituted compounds, otherwise mixtures of 5-substituted 1-aryl-1H-pyrazole-4-acetonitriles and 4-methyl-1-phenyl-1H-pyrazole-3-carbonitriles were generally obtained. Acetonitriles IIIa,b,i,l gave in excellent yields the corresponding 1-aryl-1H-pyrazole-4-acetic acids Va,b,i,l by alkaline hydrolysis. Compounds Vb,i,l showed in the writhing test appreciable analgesic properties, associated with low acute toxicity; moreover, compound VI exhibited a statistically significant antiinflammatory activity in the carrageenan-induced edema assay.  相似文献   

15.
The synthesis of 1-aryl-5-cyano-1H-pyrazole-4-carboxylic acid, ethyl esters 1 is described. Subsequent chemistry led to relatively simple and unique pyrazole derivatives. Most important of these are 1-aryl-5-(aminocarbonyl)-1H-pyrazole-4-carboxylic acids 2, which are chemical hybridizing agents in wheat and barley. The regioselective hydrolysis of 1-(3-chlorophenyl)-1H-pyrazole-4,5-dicarboxylic acid, dimethyl ester (7b) and subsequent chemistry is also described.  相似文献   

16.
It is shown that oxidation of 1-methyl-3-hydroxymethylenediazole with a solution of potassium dichromate in dilute sulfuric acid gives a 30% yield of 1-methyl-3-formylindazole. Condensation products of the latter with malonic acid, nitromethane acetophenone, hippuric acid, hydantoin, thiohydantoin, and rhodanine are obtained. An oxime and a semicarbazone are prepared.  相似文献   

17.
拟除虫菊脂是在研究天然除虫菊脂化学的基础上发展起来的一类高效低毒,广谱杀虫剂。其中,溴氰菊脂是活性较高,光稳定性较好的一种菊脂类杀虫剂, 它是具有(IRcis.αs) 构型的单一光学异构体。 生产溴氰菊脂的关键中间体是IR-cis-)二溴菊脂。本文报道利用化学剪切法将(is)-cis-菊脂转化为(IR-cis-)二溴菊脂的新方法。  相似文献   

18.
利用琥珀酸为鳌合剂的湿化学法成功合成了一系列锂离子电池正极材料LiNi1/3Mn1/3Co1/3O2,在合成过程中改变琥珀酸与金属离子摩尔比(R)并研究了这一参数对合成LiNi1/3Mn1/3Co1/3O2材料物理及电化学性质的影响.采用热重、X射线衍射、Rietveld精修、扫描电镜以及超导量子干涉仪对反应机理、材料的结构、形貌以及磁学性质进行了详细表征.得到最佳合成条件为R=1,此时LiNi1/3Mn1/3Co1/3O2的阳离子混排度最低.此外,通过Rietveld精修得到该材料阳离子混排度的结果与通过磁学方法得到的结果定量相符,如对于在R=1条件下合成的样品,Rietveld精修结果显示其阳离子混排度为1.85%,而超导量子干涉仪的测试结果为1.80%.当充放电区间为3.0-4.3V,电流密度为0.2C(1C=160mA·g-1)时,该样品的首次放电容量为161mAh·g-1,库仑效率为93.1%,经过50次循环后,容量保持率可达91.3%.  相似文献   

19.
The acid catalysed interaction in dioxan of trialkyl orthoformates with diisophor-2(7)-en-ol-3-one, diisophor-2(7)-en-ol, and their bisnor-homologues, provides the corresponding 1-alkoxy-compounds. Their structure is established by the identity of -methoxydiisophor-2(7)-en-3-one obtained by this method, and by the action of sodium methoxide on 1-chlorodiisophor-2(17)-en-3-one. The latter is regenerated from 1-methoxy(or ethoxy) diisophor-2(7)-en-3-one by the action of stannic chloride-acetyl chloride. Catalytic hydrogenation reduces the 3-keto-function in 1-alkoxydiisophor-2(7)-en-3-ones to a methylene unit; simultaneous removal of the 1-alkoxy-group in the case of the 1-isopropoxy-homologue yields the penultimate parent hydrocarbon of this series, diisophor-2(7)-ene.The combined action of silver sulphate and formic acid in concentrated sulphuric acid on 1-chlorodiisophor-2(7)-en-3-one (and its bisnor-homologue) produces the corresponding 1-carboxylic acids. These are also obtainable by the hydrolysis of the 1-cyano-compound, and are esterifiable by the standard methods.  相似文献   

20.
Seven bis-(1λ4,2-diselenol-1-ylium) tetrachloroferrates have been prepared by reaction of 1,3-diketones or 1,3-ketoaldehydes with hydrogen selenide and iron(III) chloride in ethanol saturated with hydrogen chloride. They decompose gradually in air. The corresponding 1λ4,2-diselenol-1-ylium perchlorates have been prepared by reaction of the tetrachloroferrates with perchloric acid in acetic acid and are stable. The tetrachloroferrates react with benzenediazonium tetrafluoroborate to give 6,6aλ4-diselena-1,2-diazapentalenes.  相似文献   

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