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1.
α,α-diacetyl ketene thioacetals had been investigated as odorless thiol equivalents in thia-Michael addition reaction.Under solvent-free conditions,a series of reactions between α,α-diacetyl ketene thioacetals and α,β-unsaturated ketones were carried out promoting by concentrated hydrochloric acid.The corresponding thia-Michael adducts in high yields were obtained.Furthermore,a mechanism for this thia-Michael addition reaction was proposed preliminary. 相似文献
2.
Jian Jun Li Shu Hui Jin Xiao Mei Liang De Kai Yuan Dao Quan Wang 《中国化学快报》2007,18(8):915-916
Six novel 12-alkoxycarbonylmethylene-1,15-pentadecanolides (3) were synthesized from 2-nitrocyclo-dodecanone by the Michael addition with acrolein followed by ring enlargement,Nef reaction and Wittig-Horner reaction.Their structures were confirmed by ~1H NMR,IR and elemental analysis.The preliminary bioassay showed that they have some fungicidal activity. 相似文献
3.
《中国化学快报》1992,(1)
Phenylurea reacted with dichlorophenylphosphine and aldehydesor ketones by Mannich-type reaction in anhydrous benzene to give five-mem-bered phosphorous heterocyclic compounds.However.derivatives ofα-ureidoalkylphosphonic acids were obtained as the reaction performedin glacial acetic acid. 相似文献
4.
Oxonium ylide intermediates generated fromα-diazocarbonyl compounds and water were trapped by Zn(Ⅱ)-activatedα-dicarbonyl compounds.The reaction gaveα,β-dihydroxyl acid derivatives in moderate yield. 相似文献
5.
Yu Chuan Li Si Ping Pang Yong Zhong Yu 《中国化学快报》2007,18(5):516-518
The cyclization reaction of D-aspartic acid was studied, the carboxyl groups of D-aspartic acid were protected by benzyl alcohol to give compound D-dibenzyl aspartate. Then (4R)-benzyl azetidine-2-one-4-carboxylate and meso-3,6-disubstituted piperazine- 2,5-diones were synthesized via intramolecular cyclization and intermolecular cyclization of D-dibenzyl aspartate, respectively, and their structures were confirmed by 1H NMR and MS. Both cyclization reaction conditions were also investigated in detail. 相似文献
6.
Chui Lin RONG Xin Cheng LIAO Jian Chen ZHANG Shu Xia CAO Lun LIU Yu Fen ZHAO 《中国化学快报》2005,16(9):1140-1142
Different hydroxy substituted coumarins were successfully phosphorylated with diisopropylphophite (DIPPH) by the Atherton-Todd reaction in 76-89% yields. Moreover, the reaction activities of different hydroxys of the coumarins in the Atherton-Todd reaction were studied. 相似文献
7.
YouMingWANG YuXinLI SuHuaWANG ZhengMingLI 《中国化学快报》2004,15(10):1135-1136
β-Keto-δ-valerolactones, which were obtained by reaction of acetoacetate with aldehydes or ketones, reacted with carbon disulfide, alkyl halides and a new condensation reaction was developed. The structures of the products 3 were confirmed by ^1HNMR spectra and elemental analysis. 相似文献
8.
Aspartic acid and glutamic acid with protectedα-amino andα-carboxyl groups had been used to react with the activated hydroxyl group of N-substituted 3,4-fullero pyrrolidine.The products were deprotected,affording two monofullereneα-amino acids,monofullerene aspartic acid(mFas)and monofullerene glutamic acid(mFgu).Then a bifullerene glutamic acid conjugate (bFguC)was synthesized by reaction of mFgu containing protected amino group with N-substituted 3,4-fullero pyrrolidine. 相似文献
9.
2-Phenyl-3-thioformylindolizine and 1,2-dimethyl-3-thioformylindolizine undergo a novel desulfur coupling reaction in the presence of tributylphosphine to give (E)-1,2-bis(3-indolizinyl)ethenes in high yields. The structures of products were confirmed by IR, ^1H NMR, MS, elemental analysis and single crystal X-ray diffraction analysis. The mechanisms involved in various stages of the reaction were discussed. 相似文献
10.
The reaction mechanism of phenylamine reacting with 1,4-butanediol to give N- phenylpyrrolidine was investigated with traditional transition state theory. Based on the experimental results, two reaction channels were discussed. The geometries of their reactants, products, intermediates and transition states were optimized. The possible transition State and activation energy were determined by vibrational analysis and IRC verification. And finally, the main reaction channel was given. 相似文献
11.
Jie Chen Rong Ji Dai Bin Tong Sheng Yuan Xiao Wei Wei Meng 《中国化学快报》2007,18(1):10-12
The reduction of 4-nitrophenol catalyzed by nitroreductase in the presence of NADH was investigated in this paper.4-Amino- phenol and 4-bydroxylamino-phenol were found in the reductive products.The relationship between reaction time and the reductive ratio were studied.The similar reducing ratios of 4-nitrophenol were obtained under aerobic and anaerobic conditions.The results indicated that an oxygen-insensitive reaction was proceeded in the reduction of 4-nitrophenol and nitroreductase was an oxygen- insensitive enzyme.The reductive products of 4-nitrophenol were determined by HPLC and MS. 相似文献
12.
A practical and efficient liquid-phase synthesis of 1,2,3-triazoles using poly(ethylene glycol) as support in aqueous solution was described. The title compounds, 1,2,3-triazoles 5 were obtained by a one-pot three-component 1,3-dipolar cycloaddition reaction in middle yields. In addition, a series of unexpected products 7 of Sonogashira reaction were also formed under the same condition. 相似文献
13.
CHEN Shao-rui ZHOU Xue-qin LI Wei LIU Dong-zhi .School of Chemical Engineering Technology Tianjin University Tianjin P.R.China .College of Science Hebei University of Science Technology Shijiazhuang 《高等学校化学研究》2011,(4):604-609
A series of novel 7-amide substituted-4-androstene-3,17-dione derivatives(8αa 8αh or 8βa 8βh) was synthesized from the important intermediates 5 by N-acylation and acidic hydrolysis.Compounds 5α and 5β were obtained through the reaction sequence including acetalization,allylic oxidation,oximation and reduction.The structures of the target compounds were characterized by MS,1H NMR,13C NMR and HRMS spectra and their stereo configurations were identified through DEPT(distortionless enhancement by polarization ... 相似文献
14.
Rui Li Wen Tao Wu Guai Li Wu Yuan Fan Long Min Wu 《中国化学快报》2007,18(7):788-790
3,5-Disubstituted 2-isoxazolines were oxidized to corresponding isoxazoles by nitric oxide in dichloromethane. The reaction more likely occurred via a one-electron transfer process. 相似文献
15.
6-Chloro-2-diethylaminoethyl-3(2H)-pyridazinone was synthesized by the reaction of 6-chloro-3(2H)-pyridazinone and 2-diethylamionethyl chloride reaction in methylbenzene.Then the structure was characterized by means of ^1H NMR,IR,UV.By the method of ab initio HF and density functional theory(DFT) BeLYP,the geometric structures of the reagent intermediate,the product and its isomer were optimized and their total energies were calculated,The properties for the frontier molecular orbitals and the rules for energy distribution were analyzed systematically.It was shown that the energy of the nitrogen alkyl compound is lower than that of the oxy alkyl compound and the former is stable than the latter.This result is in accordance with the fact that 6-chloro-2-diethylaminoethyl-3(2H)-pyridazinone is synthesized by the reaction of 6-chloride-2-diethylaminoethyl-3(2H)-pyridazinone and 2-diethylaminoethyl chloride. 相似文献
16.
Chang Xie Hong Xia Li Ming Guo Liu Ming Wu Ding 《中国化学快报》2008,19(5):505-508
4(3H)-Quinazolinones have been synthesized from poly(ethylene glycol) (PEG) supported aza-Wittig reaction. 2-Dialkylamino- 4(3H)-quinazolinones 6 were synthesized efficiently by reaction of secondary amine with PEG-supported carbodiimides 4, which were obtained from aza-Wittig reaction of PEG-supported iminophosphoranes 3 with isocyanates. 相似文献
17.
DIAKITE Kahirou 《高等学校化学研究》2010,26(2):300-303
The non-isothermal decomposition kinetics of LiClO4 in flow N2 atmosphere was studied.TG-DTA curves show that the decomposition proceeded through two well-defined steps below 900°C,and the mass loss was in agreement with the theoretica1 value.XRD profile demonstrates that the product of the thermal decomposition at 500°C is LiCl.For the decomposition kinetics study,the activation energies calculated with the Friedman method were considered as the initial values for non-linear regression and were used for verifying the correctness of the fitted models.The decomposition process was fitted by a two-step consecutive reaction:extended Prout-Tompkins equation[Bna,f (α) is (1?α)nα a] followed by a 1th order reaction(F1).The activation energies were (215.6±0.2) and (251.6±3.6) kJ/mol,respectively.The exponentials n and a for Bna reaction were (0.25±0.05) and (0.795±0.005),respectively.The reaction types and activation energies were in agreement with those obtained from the isothermal method,but the exponentials were optimized for better fitting and prediction. 相似文献
18.
Synthesis of 2-methylpyrazine from cyclocondensation of ethylene diamine and propylene glycol over promoted copper catalyst 总被引:1,自引:0,他引:1
The 2-methylpyrazine was synthesized by catalytic reaction of ethylene diamine and propylene glycol at 380 ℃. The alumina supported copper catalysts with promoter were prepared by impregnation method, characterized by ICP-AES, BET and TPR. The results demonstrated that the dehydrogenation was improved by addition of chromium promoter. The selectivity of 2-methylpyrazine reached 84.75%, while the conversions of reactants were also enhanced. 相似文献
19.
CHEN Qiu-yun ZHANG Rong-xian LIU Qing-shan Schofield Christopher 《高等学校化学研究》2007,23(3):284-288
Fourteen novel compounds were synthesized and characterized by using NMR and ESI-MS methods. The bioactivities of the four novel 4-Ar-2-oxo-glutaric acids were studied by using the LC-MS method. The experimental results show that 3-nitrobenzyl-2-oxo-glutaric acid is a mild inhibitor for the hydroxylation reaction catalyzed by PHD2. The decarboxylated peak for 3-fluorobenzyl-2-oxo-glutaric acid was observed by using the negative LC-MS method, indicating that it can be used as a mild cosubstrate to replace 2-OG, but this is possible only in the presence of the prime peptide CODD 19 mer. 相似文献
20.
Rui Fang GUAN Chuan Jian ZHOU Sheng Yu FENG David J. BERG Stephen R. STOBART 《中国化学快报》2006,17(3):293-295
Carbosilane dendrimers with p-bromophenyl core were synthesized by alternating Grignard and hydrosilylation reaction. And the α-naphthalenyl was connected to the core by the Suzuki coupling reaction. A new carbosilane dendrimer with big π-conjugated structure [4-(naphthalen-l-yl)phenyl core] was given. It shows Suzuki coupling reaction is an effective and powerful core-functionalization method and the satisfactory result can be obtained through prolonging the reaction time with the increase of the generation of dendrimer. 相似文献