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1.
The heat effects of solution of diethylenetriamino-N,N,N′,N″,N″-pentaacetic acid (H5dtpa) in water and solutions of potassium hydroxide were determined at 298.15 K by direct calorimetry. The standard enthalpies of formation of H5dtpa and its dissociation products were calculated.  相似文献   

2.
Syntheses, structural studies, and thermochemical transformations of fluorosilicic acid complexes with N,O-ambidentate ureas, hydrazides of carboxylic acids, and their thioderivatives are presented in a general form.  相似文献   

3.
A solution of acid chlorides 3a-g in DMF solvent was refluxed to give N,N-dimethylamides 4a-f and 5g in excellent yields.  相似文献   

4.
An improved synthesis of N,N′‐disuccinimidyl carbonate (DSC) is described where α‐pinene is utilized as an efficient scavenger of HCl liberated during the reaction of N‐hydroxysuccinimide with triphosgene in THF. The α‐pinene hydrochloride formed is soluble in THF and gives very pure DSC in good yields.  相似文献   

5.
Russian Journal of General Chemistry - Polarity of N,N-dibutylamide of dibutylphosphorylacetic acid has been determined and its conformational analysis has been carried out by the methods of dipole...  相似文献   

6.
Navjeet Kaur 《合成通讯》2013,43(15):1711-1742
The development of new strategies for the synthesis of small-sized heterocycles has remained a highly attractive but challenging proposition. An overview of the application of microwave irradiation to the synthesis of five-membered heterocyclic compounds containing three and four nitrogen atoms is presented, focusing on the developments in the past 5–10 years. This contribution covers the literature concerning the total synthesis of N,N,N- and N,N,N,N-heterocycles. The literature data are summarized based on the size and type of cycles.  相似文献   

7.
A new diamide N,N,N′,N′-tetrahexylmalonamide (THMA) was synthesized, characterized and used in the extraction of U(VI) from nitric acid solutions. N,N,N′,N′-tetrabutylmalonamide (TBMA) was also studied to test the steric hindrance. Factors affecting this extraction system, the concentration of the extractant, aqueous nitric acid and NaNO3 and the temperature were investigated. The IR spectral study was also made of the extracted species.  相似文献   

8.
Conclusions The syn-isomers of N,N,N-trifluorobutyramidine and N,N,N-trifluoromonochloroacetamidine are isomerized in the presence of HCl to the anti-form. The isomerization of the syn-isomer of N,N,N-trifluoromonochloroacetamidine also proceeds in the presence of ethanol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2159–2160, September, 1973.  相似文献   

9.
李高亮  何辉 《应用化学》2010,27(8):916-923
分别在高氯酸和硝酸介质中研究了N,N-二甲基羟胺(DMHAN)与HNO2的反应动力学,通过考察溶液酸度、还原剂浓度、离子强度和温度等因素对反应过程的影响,获得高氯酸介质中反应动力学速率方程为-d[HNO2]/dt=k[DMHAN][HNO2],在18.5 ℃,离子强度μ=0.73 mol/L时,反应速率常数k=(12.8±1.0) mol/(L·min),反应活化能Ea=41.5 kJ/mol。 在硝酸介质中DMHAN与HNO2的反应比较复杂,硝酸浓度较高时,硝酸将参与反应重新生成HNO2,且硝酸浓度越大,HNO2的生成速度越快,HNO2与DMHAN的反应是自催化氧化的。 对DMHAN与HNO2的反应产物进行了分析,并推导了硝酸体系中DMHAN与HNO2的反应机理。  相似文献   

10.
N,N'-Dialkylcyclohexane-1,2-diimines react with trivalent phosphorus acid chlorides to give, depending on the structure of the organophosphorus reagent and reaction conditions, either 1,3,2-diazaphospholanes (three-coordinate phosphorus) containing the cyclohexadiene fragment in positions 4 and 5, or 1,3,2-diazaphospholines (four-coordinate phosphorus).  相似文献   

11.
Chemistry of Heterocyclic Compounds - Novel pentasubstituted pyrroles containing a propanoic acid fragment in position 1 were obtained by the reaction of arylglyoxals, N,Ndimethylbarbituric and...  相似文献   

12.
N,N-dinitrosulfodiamides are formed in the nitration of sulfodiamides with concentrated nitric acid or nitronium borofluoride, and also on substitutional nitration of the corresponding N,N-di-tert.-butyl derivatives with those reagents. Sulfuryl chloride reacts with the disodium salt of ethylene N,N-dinitramine to produce 2,5-dinitro-1,2,5-thiadiazolidine-1,1-dioxide. The corresponding N-nitrosulfamides are formed when nitramine salts react with methane sulfochloride.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1812–1815, August, 1989.  相似文献   

13.
Poly(N,N??-dibromo-N-ethyl-benzene-1,3-disulfonamide) [PBBS] and N,N,N??,N??-tetrabromobenzene-1,3-disulfonamide[TBBDA] were used as efficient reagents for conjugate addition of indole and pyrrole with ??,??-unsaturated ketones and also, double-conjugate 1,4-addition of indoles to dibenzylidenacetones.  相似文献   

14.
The reaction of organolithium reagents (alkyl, aryl, heteroaryl) with N,N,N′,N′-tetramethylsuccinamide at 0 °C gives good yields of the corresponding 1,4-diketones.  相似文献   

15.
The isomers of the nitrogen-substituted fullerenes (azafullerenes) C19N, C59N, C69N, and C75N are examined using all-electron Gaussian atomic orbital basis density functional theory, to determine the doublet radical geometries and hyperfine coupling constants. We find that the inaccuracy of previously calculated hyperfine coupling constants of C59N resulted from a poor treatment of the geometry optimization. We find that UB3LYP minimization of the radical geometry in the 6-31G basis, followed by single-point evaluation of the hyperfine constants in which an expanded basis is used on the atomic sites of interest, forms an efficient compromise between computational cost and accuracy with respect to experimental hyperfine constants. Using this approach, we assign the hyperfine signals observed in experiments on the C69N radical by calculating the hyperfine coupling constants for all five of the isomers and examine the electron spin density distribution. Finally, we present predicted hyperfine coupling constants for the isomers of C19N and C75N for use in the interpretation of future experiments.  相似文献   

16.
Pyridine, pyridine imine, and bipyridine imine ligands functionalized by a phenol have been synthesized and characterized, in many cases by X-ray diffraction. Several of these N-, N,N-, and N,N,N,-ligands have been grafted onto the surface of phosphorhydrazone dendrimers, from generation 1 to generation 3. The complexation ability of these monomers and dendrimers towards palladium(II) has been assayed. The corresponding complexes have been either isolated or prepared in situ. In both cases, the monomeric and dendritic complexes have been tested as catalysts in Heck couplings and in Sonogashira couplings. In some cases, a positive dendritic effect has been observed, that is, an increase of the catalytic efficiency proportional to the dendrimer generation.  相似文献   

17.
以2,7-二溴咔唑为原料经过N-烷基化、Suzuki偶联反应、Buchwald-Hartwig偶联反应合成了有机发光二极管(OLED)空穴传输材料N,N’-二苯基-N,N’-二(9,9-二甲基芴-2-基)-9-己基-(4,4’-二胺基苯基)咔唑,利用NMR、IR和熔点等分析方法对产物结构进行了表征,并通过TG、UV-Vis及荧光光谱研究了物质的热稳定性和光学性能。  相似文献   

18.
In contrast to the neutral macrocycle [UN*(2)(N,C)] (1) [N* = N(SiMe(3))(3); N,C = CH(2)SiMe(2)N(SiMe(3))] which was quite inert toward I(2), the anionic bismetallacycle [NaUN*(N,C)(2)] (2) was readily transformed into the enlarged monometallacycle [UN*(N,N)I] (4) [N,N = (Me(3)Si)NSiMe(2)CH(2)CH(2)SiMe(2)N(SiMe(3))] resulting from C-C coupling of the two CH(2) groups, and [NaUN*(N,O)(2)] (3) [N,O = OC(═CH(2))SiMe(2)N(SiMe(3))], which is devoid of any U-C bond, was oxidized into the U(V) bismetallacycle [Na{UN*(N,O)(2)}(2)(μ-I)] (5). Sodium amalgam reduction of 4 gave the U(III) compound [UN*(N,N)] (6). Addition of MN(3) or MCN to the (N,C), (N,N), and (N,O) metallacycles 1, 4, and 5 led to the formation of the anionic azide or cyanide derivatives M[UN*(2)(N,C)(N(3))] [M = Na, 7a or Na(15-crown-5), 7b], M[UN*(2)(N,C)(CN)] [M = NEt(4), 8a or Na(15-crown-5), 8b or K(18-crown-6), 8c], M[UN*(N,N)(N(3))(2)] [M = Na, 9a or Na(THF)(4), 9b], [NEt(4)][UN*(N,N)(CN)(2)] (10), M[UN*(N,O)(2)(N(3))] [M = Na, 11a or Na(15-crown-5), 11b], M[UN*(N,O)(2)(CN)] [M = NEt(4), 12a or Na(15-crown-5), 12b]. In the presence of excess iodine in THF, the cyanide 12a was converted back into the iodide 5, while the azide 11a was transformed into the neutral U(V) complex [U(N{SiMe(3)}SiMe(2)C{CHI}O)(2)I(THF)] (13). The X-ray crystal structures of 4, 7b, 8a-c, 9b, 10, 12b, and 13 were determined.  相似文献   

19.
Conclusions Syntheses are reported for asymmetric N,N-disubstituted N.N-dinitromethylenediamines by the Mannich reaction from N-nitroalkylamines, formaldehyde, and 2-fluoro-2,2-dinitro-ethylamine in methanol or ethanol.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 721–723, March, 1989.  相似文献   

20.
INTRODUCTIONThe atom transfer radical polymerization (ATRP) has become an important method for preparing well-definedmacromolecules. This technique offers control over the molecular weights, the chain end functionalities, and thechain architectures[1-12]. It has been used extensively for the preparation of homopolymers, block, and randomcopolymers[13-39], for the preparation of organic/inorganic hybrid materials[40-54], as well as for combining variousother living polymerization methods …  相似文献   

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