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

3.
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   

4.
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   

5.
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   

6.
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   

7.
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   

8.
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   

9.
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   

10.
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   

11.
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   

12.
ls-反式第一菊酸经甲酯化、臭氧化、还原和差向异构化制得1R-顺式皆醇酸内酯,再经过中间产物皆硫醚酸被转变成1R-顺式皆醛酸半缩醛内酯。  相似文献   

13.
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   

14.
The preparative possibilities of syntheses based on pyrrolanthrone-1-carboxylic acid were studied. Methylation of the acid or its ester leads to N-methylpyrrolanthrone-1-carboxylic acid esters. The esters were converted to amides and hydrazides, and the latter were converted to 1-amino derivatives through the azides. The indicated transformations and decarboxylation in phosphoric acid give the products in high yields.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 785–788, June, 1978.  相似文献   

15.
A group of 2-alkyl-1H-imidazo[4,5-b]pyrazines were prepared by condensing diamonpyrazines with acid, acid chloride or acid anhydride.  相似文献   

16.
The interaction of the antifungal pharmaceutical agent fluconazole with salicylic acid in acetonitrile solution yields the 1:1 cocrystal 2‐(2,4‐difluorophenyl)‐1,3‐bis(1H‐1,2,4‐triazol‐1‐yl)propan‐2‐ol–2‐hydroxybenzoic acid (1/1), C13H12F2N6O·C7H6O3. The asymmetric unit consists of one molecule of fluconazole and one molecule of salicylic acid, both in their neutral forms. Both crystal agents form head‐to‐tail hydrogen‐bonded dimers, which are further connected into hydrogen‐bonded extended zigzag tapes propagating along the ac diagonal.  相似文献   

17.
氨基磺酸催化合成-萘乙酸甲酯   总被引:1,自引:0,他引:1  
氨基磺酸能够代替硫酸作为酯化催化剂。在氨基磺酸存在下,由1-萘乙酸和甲醇酯化合成了高收率的1-萘乙酸甲酯。研究了反应的影响因素和催化剂的重复使用性能。当1-萘乙酸、甲醇和氨基磺酸的质量比为1:10:1,回流反应5h时,酯收率达97.5%。  相似文献   

18.
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   

19.
1-Piperidino-1-trimethylsilyloxycyclopropane and the corresponding 1-hydroxy-1-piperidinocyclopropane are conveniently perpared from the piperidide of 3-chloropropionic acid. Reactions of these cyclopropanone equivalents with various nucleophiles are described.  相似文献   

20.
The direction of the reaction of 4-bromo-1,3-diphenyl-2-buten-1-one (γ-bromodypnone) with hydrazines depends on the nature of the substituent they contain. Reaction with 1-methylhydrazinium hydrosulfate gives 1-methyl-3,5-diphenylpyridazin-1-ium bromide but carboxylic acid hydrazides give N-(2,4-diphenyl-1H-pyrrol-1-yl)carboxylic acid amides. γ-Bromodypnone and phenylhydrazine give both 1,3,5-triphenyl-1,4-dihydropyridazine and N,2,4-triphenyl-1H-pyrrol-1-amine (15%). 1-(2,4-Dinitrophenyl)hydrazine gives the 2,4-dinitrophenylhydrazone of (Z)-4-bromo-1,3-diphenyl-2-buten-1-one. Condensation of 2,4-diphenyl-1H-pyrrol-1-amine with aromatic aldehydes readily leads to N-(arylmethylidene)-2,4-diphenyl-1H-pyrrol-1-amines and alkylation with methyl iodide gives N,N-dimethyl-2,4-diphenyl-1H-pyrrol-1-amine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–414, March, 2009.  相似文献   

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