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1.
The reaction of N-polyfluorophenylcarbonimidoyl dichlorides with primary and secondary aliphatic and aromatic amines have been studied. With primary aliphatic amines, the reactions led to carbodiimides or guanidines, depending on the amount of amine. The carbodiimides obtained reacted with amines to form guanidines. The reactions with primary aromatic amines produced only triarylguanidines. N-Pentafluorophenyllcarbonimidoyl dichloride (I) reacted with tetrafluoro-o-phenylene diamine to give 2-pentafluoroanilino-4,5,6,7-tetrafluorobenzimidazole. Polyfluorinated benzimidazole derivatives were also produced by the thermolysis of polyfluorinated triarylguanidines. Heating of N1,N2,N3-tris(pentafluorophenyl)guanidine with K2CO3 in dimethylformamide led to 1,2,3,4,7,8,9,10-octafluoro-5-pentafluorophenyl-5H-benzimidazol[1,2-a]benzimidazole. N-Polyfluorophenylcarbonimidoyl dichlorides reacted with various secondary amines already at room temperature giving N-polyfluorophenylchloroformamidines in high yields. Elevated temperature and prolonged reaction time led to formation of N-polyfluorophenylguanidines. Kinetics and mechanism of the reactions of N-polyfluorophenylcarbonimidoyl dichlorides with primary and secondary amines in acetonitrile at 25°C have been studied. The reactions have been found to proceed by a bimolecular nucleophilic addition-elimination mechanism via a tetrahedral intermediate. Possible reasons of formation of different products in the above transformation are discussed in terms of this mechanism.  相似文献   

2.
N-Cyano monoaza crown ethers were prepared by the reaction of cyanamide with oligoethylene glycol dichlorides or ditosylates in the NaH/DMSO reaction system and led to the derivatives.  相似文献   

3.
Diaryltellurium diacetates have been prepared in excellent yields by the oxidation of diaryltellurides with lead tetraacetate and also by the reaction of diaryltellurium dichlorides with silver acetate. Hydrolysis, reduction and exchange reactions of these derivatives and their spectral data are described.  相似文献   

4.
Five- and Six-Membered Cyclic Phosphonic Diamides, Thioester-amides and Spirobi[oxazaphospholes] By reaction of the 1,2-diaminobenzene derivatives 1a–d with the phosphonoyl dichlorides 2a–g , the 1,3-dihydro-1,3,2-benzodiazaphosphol-2-ones 4a–q are obtained. The phosponoyl dichlorides 2a–e, 2g , and 2h yield with naphthalene-1,8-diamines ( 5 ) the diazaphosphinones 6a–g under similar reaction conditions. The thiazaphosphole oxides 9a–d are accessible by reaction of the phosphonoyl dichlorides 2a–d with 2-aminobenzenethiol ( 7 ). Unexpectedly, the reaction of the dichlorides 2a and 2b with 2-aminophenol ( 10 ) led to the spirobi[oxazaphospholes] 13a and 13b , respectively.  相似文献   

5.
Highly chlorinated amine derivatives can be prepared by the high-temperature chlorination of amines and amine derivatives. Essential for the success of this reaction is an adequate temperature control suited to the constitution of the amines. In many cases the chlorination products achieve stability by cleavage reactions with formation of the imidic acid chloride or isocyanide dichloride grouping. Cyclic compounds are formed under special conditions. The chlorination process described can be used to obtain e.g. polychloroaryl and polychloroalkyl isocyanide dichlorides, polychloroaryl and polychloroalkyl imidic acid chlorides, and polychloroheterocyclic compounds.  相似文献   

6.
本文报导烷基环戊二烯基钠与金属氯化物反应合成钛、锆和铪的双(烷基环戊二烯基)金属二氯化物以及通过卤素交换制备双(烷基环戊二烯基)钛的二氟化物的方法。同时报导了以上的二氯化物与酚反应制备的一系列芳氧基金属衍生物。本文还讨论了金属、卤素、烷基对于质子化学位移的影响并探讨了主要红外吸收峰的归属。  相似文献   

7.
An efficient semisynthetic preparation of des-28-(cyclohexyl)methylene-28-oxo-ascomycin derivatives starting from 24,33-O-bis(tert-butyldimethylsilyl)-ascomycin (1) is described. The strategy for preparing 28-oxo-ascomycin derivatives involves the reduction of C-22 carbonyl group, followed by 5-endo-cyclization of the resulting C-22 alcohol with the C-19/C-20 double bond using an oxymercuration reaction; ozonolysis of the C-28/C-29 double bond and regeneration of the C-19/C-20 double bond. Further, the 20-mercury-substituted ascomycin derivatives could be reduced to the corresponding metal free cyclic ethers using n-Bu3SnH.  相似文献   

8.
The readily obtainable isocyanide dichlorides can be used as starting materials for the preparation of many types of substances. Exchange reactions yield numerous derivatives of formic and carbonic acids, while heterocyclic products have been obtained by reaction with bifunctional partners. The present article deals not only with reactions that are known from the literature but also with the author's own work, some of which has not been published before.  相似文献   

9.
以硼试剂B(C6F5)3为催化剂, 吲哚类化合物与芳香醛为底物, 经过脱除一分子水的过程, 简洁有效地制得了一系列二吲哚基甲烷类化合物. 该方法的模板反应在最优条件下可以实现快速转化, 底物范围适用性较广泛, 可以适用一系列取代基和官能团. 该研究发展了无过渡金属参与条件下直接制备二吲哚甲烷类化合物的简单策略, 其反应副产物为水, 反应条件温和, 可以实现目标化合物的有效合成.  相似文献   

10.
以易得的1-金刚烷甲酸为原料, 合成了一系列对称桥头二取代金刚烷衍生物. 由1-金刚烷甲酸经Koch-Haaf羰基化反应得到1,3-金刚烷二甲酸(1); 化合物1经还原得到1,3-金刚烷二甲醇(2); 化合物2在HBr-ZnBr2体系中经溴代反应得1,3-二(溴甲基)金刚烷(3); 同时经Apple-Lee反应将化合物2转化得到1,3-二(氯甲基)金刚烷(4). 采用红外光谱和核磁共振氢谱等手段表征了产物的结构, 提出了可能的反应机理, 并对合成条件进行了优化.  相似文献   

11.
2,3,4,5-四取代-顺-2,3-二氢呋喃立体选择性合成方法的研究   总被引:1,自引:1,他引:0  
研究了3种合成2甲氧羰基3芳基4乙酰基5甲基顺2,3二氢呋喃(7)的方法.方法1:用甲氧羰基亚甲基三苯基胂(5)与3(取代苯甲叉)2,4戊二酮(6)反应;方法2:用溴化甲氧羰基甲基三苯基胂(4)在碳酸钾存在下与戊二酮6反应;方法3(分步一锅法):三苯基胂(2)与溴代乙酸甲酯(3)加热反应,生成的产物不经分离,冷却至室温,加入碳酸钾和6继续反应.  相似文献   

12.
Vinylation and 91Zr N.M.R. Spectra of substituted Zirconocene Dichlorides Substituted zirconocene dichlorides react with vinyl lithium with formation of zirconacyclopent-2-enes, Cp2ZrCH = CHCH2CH2, or zirconocene butadiene complexes, Cp2Zr(C4H6). The compounds obtained were characterized by their 1H and 13C n.m.r. spectra. The 91Zr n.m.r. chemical shifts of substituted zirconocene dichlorides correlate with the bond angles Cp′? Zr? Cp′ and Cl? Zr? Cl respectively. They can be used to estimate the reaction behaviour of zirconocene dichlorides.  相似文献   

13.
MA Potopnyk  P Cmoch  S Jarosz 《Organic letters》2012,14(16):4258-4261
A convenient route to macrocyclic diamide-linked macrocyclic derivatives with a sucrose scaffold is presented. Reaction of sucrose based amines (o- and m-) with acid dichlorides afforded the monomeric macrocycles in excellent yields, while reaction of the p-amines also provided dimeric products.  相似文献   

14.
The behaviour of tetraarylstannanes, R4Sn (R = C6H5CH2, C6H5, o-, m-, p-CH3C6H4), towards SO2 under various conditions has now been studied in detail. Compared to aliphatic tetraorganostannanes, the variability of the reaction products is much less, so that in nearly all cases only disulfinates, R2Sn(O2SR)2, are formed. The aromatic tin(IV) mono-, di- and tri-sulfinates are also obtained by metathetical reaction between the corresponding organotin halides and sodium sulfinates. A unique feature of triaryltin chlorides, R3SnCl (R = C6H5, o-, m-, p-CH3C6H4), is their disproportionation in liquid SO2 leading to disulfinates, R2Sn(O2SR)2, and dichlorides, R2SnCl2. (p-CH3C6H4)2SnCl2, under more efficient conditions, also accepts SO2 forming (p-CH3C6H4SO2)2SnCl2. The structural investigations of the newly prepared compounds are carried out on the basis of their IR and 1H NMR spectra.  相似文献   

15.
The reaction of the metallocene dichlorides Cp2MCl2 (Cp = η5-C5H5; M = Ti, Zr, Hf, Mo, W) and Cp2′TiCl2 (Cp′ = η5-C5H4CH3) with equimolar amounts of dilithium-benzene-o-diselenolate, 1,2-(LiSe)2C6H4, gives the chelate complexes Cp2M(Se2C6H4) (M = Ti (I), Zr (II), Hf (III), Mo (IV), W (V)) and Cp2′Ti(Se2C6H4) (VI). CpTiCl3 reacts with 1,2-(LiSe)2C6H4 to give CpTiCl(Se2C6H4) (VII). The ring inversion activation parameters for I–VI can be determined by means of temperature-dependent 1H NMR spectroscopy in solution. The fragmentation behaviour of I–VII in the mass spectrometer has been investigated by pursuing metastable transitions, using linked-scan techniques.  相似文献   

16.
Subject index     
Elementary sulfur and selenium combine (in boiling heptane) with [(tBuCp)2-Zr(C6H4R)2] (Cp = η5-C5H4; R = OCH3) to give the corresponding dichalcogenophenylenezirconocene. With tellurium, the reaction proceeds only at lower temperature (in boiling hexane), affording the first ditellurophenylenezirconocene. As no metallacycle was obtained with the Cp ligand or when the metal is Hf, complexes of the general type [(RCp)2MSe2C6H4-o] (M = Ti, Zr, Hf; R = H, t-Bu, (CH3)5) have been synthesized by allowing metallocene dichlorides to react with potassium benzenediselenolate, prepared by cleaving [(t-BuCp)2ZrSe2C6H4-o] with t-BuOK.  相似文献   

17.
A new method for the synthesis of functional enamines from β,β-dicyanostyrene derivatives and N-bromosaccharin(NBSA) was developed. In the presence of Na2CO3, the the reaction of β,β-dicyanostyrene derivatives with NBSA can generate the corresponding enamines smoothly in a mixed solvent of dichloromethane and N,N-dimethylformamide (DMF)(volume ratio 1:1) at 50℃. The reaction of 14 kinds of β,β-dicyanostyrene derivatives with NBSA was investigated. Screened olefins afforded the corresponding enamines in good to excellent yields(up to 94%), indicating that the method has a wide adaptability for the substrate. The catalyst used is inexpensive and stable for storage. The amino groups of all products in their structures are on the α-position of products, revealing the reaction has an excellent regioselectivity. The possible pathway involving aminobromination of β,β-dicyanostyrene derivative with NBSA first and then elimination of HBr process in one pot has been proposed. The structures of all products were confirmed by 1H NMR, 13C NMR and HRMS analysis.  相似文献   

18.
Alkylation of 4-ethoxy-2-hydroxypyrimidines (10a, b), via their anions, provides a convenient procedure for preparing N1-substituted derivatives. Reaction of 10a, b with t-butyl 4-bromo-2-benzyloxycarbamidobutyrate (17) gives good yields of the N1-alkylated products 18a, b. The latter have been converted to uracil- (20a), thymine- (20b) and cytosine- (21) substituted -aminobutyric acids.  相似文献   

19.
An easy and efficient method for the synthesis of multisubstituted cyclopropane derivatives from electron-deficicent alkenes with 2-bromo-1,3-propanedione compounds was described. For this method, ethyl α-cyanocinnamate derivatives 1 and β,β-dicyanostyrene derivatives 4 can all smoothly react with 2-bromo-1,3-propanedione compounds 2 to afford the corresponding multisubstituted cyclopropane derivatives 3 and 5 in good to excellent yields(up to 100%) promoted by anhydrous K3PO4 in DMF at room temperature, respectively. A possible mechanism of this reaction was proposed. Structures of all the products were confirmed by 1H NMR, 13C NMR and HRMS.  相似文献   

20.
A new series of dextrorotatory derivatives of 1R,3RS,5S-1,8,8-trimethyl-2,4,3-diazaphosphabicyclo [3.2.1] octane with a newly formed chiral phosphorus atom has been prepared by an asymmetric reaction of (+)-cis-1R,3S-1,2,2-trimethyl-1,3-cyclopentadiamine with some thiophosphoryl dichlorides. The optically active products consisted of two unequal amounts of diastereomers,(1R, 3R, 5S) isomers and(1R, 3S, 5S) isomers. Two regioselective reactions took place when phenoxy thiophosphoryl dichloride and N,N-dialkylamino thiophosphoryl dichlorides were chosen as the reagents for the reaction. The content of (1R, 3R, 5S) isomers in the product was over 90% for the former and there were only (1R, 3S, 5S) isomers obtained for the latter.  相似文献   

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