首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A facile and efficient synthesis of highly substituted pyrroles has been achieved by a one-pot three-component coupling reaction of aldehyde, amine and nitroalkane by triethyl orthoformate.  相似文献   

2.
Abstract

Diels Alder reaction provides an easy and general access to functionalized Δ3 phosphabenzenes after aromatization with the possibilities of introducing the functional group either with the diene or the phosphaalkene.  相似文献   

3.
The adducts produced in the reaction between 2,6‐dimethylphenyl isocyanide and acetylenic esters were trapped by 3‐chloroacetylacetone, dialkyl 2‐chloromalonates, or dimethoxy methoxymalonate to produce highly functionalized 1‐azadienes in good yields.  相似文献   

4.
《合成通讯》2013,43(8):1059-1066
Abstract

The 3β‐acetoxy‐6β‐(3,5‐dioxo‐4‐phenyl‐[1,2,4]triazolidin‐1‐yl)cholest‐4‐ene structure has been assigned to a single product of the reaction of cholesteryl acetate with 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione in Et2O solution, mediated by LiClO4.  相似文献   

5.
The tandem dual C−H amination of tetrahydroquinoxalines with free amines under aerobic copper catalysis conditions has been demonstrated. The synthetic protocol proceeds with good substrate and functional group compatibility, mild reaction conditions, short reaction time, the use of the naturally abundant [Cu]/O2 catalyst system, excellent chemoselectivity and synthetic efficiency, and with no need for the pre-installation of specific aminating agents, which offers a practical platform for the rapid and diverse synthesis of diaminoquinoxalines. Moreover, this work has shown the potential of single-electron-oxidation-induced C−H functionalization of N-heterocycles, and its application in the development of optoelectronic materials.  相似文献   

6.
Flurbiprofen 1, an excellent nonsteroidal antiinflammatory drug, was synthesized in 5 steps in 69% overall yield. The key step of constructing the biaryl fragment was successfully achieved via Pd/C-catalyzed Suzuki coupling reaction in water using sodium tetraphenylborate as phenylation reagent.  相似文献   

7.
Edith Holtz 《合成通讯》2013,43(17):2959-2966
5‐Cyano‐1,3‐dioxoalkanes were prepared by reaction of 1,3‐dicarbonyl dianions with bromoacetonitrile.  相似文献   

8.
《合成通讯》2013,43(13):1803-1808
Abstract

Water‐soluble fullerenol was conveniently synthesized via the direct solvent‐free reaction of fullerene with a mixture of H2O2 and NaOH under grinding conditions in air at room temperature. This practical method provides a novel and efficient access to water‐soluble fullerenol in excellent yield.  相似文献   

9.
1-8-Diazabicyclo[5.4.0]undec-7-ene(DBU)‐catalyzed Michael addition of nitroalkanes to dicyclopentadienone (1) followed by flash vacuum pyrolysis (FVP) provided a high‐yielding synthesis of extremely pure 4‐nitroalkyl cyclopentenones (3). The optimized Nef reaction of the nitro adducts (2) provided 4‐ketoalkyl cyclopentenones (5) in the similar way.  相似文献   

10.
A practical green chemistry procedure for synthesis of 3,4‐dihydropyrimidin‐2(1H);‐ones in good yields was successfully carried out in micellar systems according to the Biginelli reaction using β‐ketoester, urea and appropriate aromatic aldehyde in the presence of CuCl2 · H2O as catalyst. The advantages of this method involved the broader application scope of substrates, the more environmental friendly process and the low‐cost of the Lewis acid catalyst.  相似文献   

11.
A stable diamino thiophene was synthesized in high purity with a three‐fold increase in yield over previous reports via simple crystallization using inexpensive reagents.  相似文献   

12.
王磊  李品华等 《中国化学》2003,21(3):222-224
Aromatic amines were prepared in good yields by a novel reduction of aromatic nitro compounds with tellurium metal in near-critical water at 275 ℃。  相似文献   

13.
The Darzens condensation reaction of aromatic aldehydes with phenacyl chloride proceeded very efficiently in a water suspension medium in the presence of triethylbenzylammonium chloride and only trans-2,3-epoxy-1,3-diaryl-1-propanones were formed which can be isolated simply by filtration.The structures of these compounds were confirmed by elemental analysis,IR and ^1H NMR spectra.Therir configurations are in agreement with that of the same compounds reported in the literature.Compared to the classical Darzens condensation,this new method has the advantages of good yields,high stereoselectivity,low running cost inexpensive and environmentally benign procedure.  相似文献   

14.
IntroductionPyrrolesareimportantsynthetictargetssincetheyareappliedasprecursorstomanyusefulclassesoforganiccom poundssuchasporphyrinsandalkloids.1Severalsubstitutedpyrroleshavepotentialapplicationasfungicidsandbacteri cidesandasactivecomponentsofnonsteroidalanti inflamma torydrugsinhibitinghumancyclooxygenase.2 ,3Inaddition ,aminoacidssuchasprolineandhydroxyprolinealsocontainthehydrogenatedpyrroleringthatisapyrrolidineframework .Althoughthereareanumberofpotentiallyusefulmethodsforthesynthesiso…  相似文献   

15.
A convenient, fast, efficient, and ecofriendly synthesis of metal‐free phthalocyanines from various substituted phthalonitriles in different hydroxyalkylammonium ionic liquids in the presence of 1,8‐diazabicyclo‐[5,4,0]‐undec‐7‐ene (DBU) is reported in moderate yields. The effect of concentration of DBU and temperature on the synthesis of phthalocyanine in N‐(2‐hydroxyethyl)‐N,N‐dimethylbutylammonium bromide ionic liquid has been examined, and the ionic liquid has been recovered and reused conveniently.  相似文献   

16.
High‐yielding syntheses of an unpublished series of 2‐thioxo‐imidazolidin‐4‐ones 6 bearing an N‐ethoxycarbonyl and amidyl moieties an N1 and C5, respectively, are reported. These derivatives were obtained by intramolecular cyclization of 3‐ethylhydrazinoacetate 3,4‐dihydro maleimides 4 in the presence of ethyl or phenylisothiocyanate 2 under neutral conditions.  相似文献   

17.
Ethyl α‐cyano‐β‐(1‐chloro‐3,4‐dihydronaphthalene‐2‐yl) acrylate (2) was prepared by the Knoevenagel condensation of 1 with ethyl cyanoacetate. Compound 2 was used as the key intermediate to prepare Schiff bases (3a, b), benzo[c]acridine (4), naphthyl thiopyrimidine (5), and pyrazolo[2,3‐a]‐benzo[h]quinazoline (6) derivatives through its reaction with hydrazines, p‐ansidine, thiourea, and 3,5‐diamino‐4‐phenylazopyrazole, respectively. Base‐catalyzed cyclocondensation of 1 with hippuric acid gives oxazolone derivative (7). Reaction of compound 7 with aniline gave imidazolone derivative (9). Treatment of compound 1 with different types of diaminopyrazoles gave 6,7‐dihydro‐pyrazolo[2,3‐a]‐benzo[h]quinazoline (1013) derivatives. The multicomponent reaction of compound 1 with pyrazolone and malononitrile in the presence of ammonium acetate furnished pyrazolo[3,4‐b]‐benzo[h]quinoline (14) while in the presence of piperidine afforded benzo[h]chromeno[2,3‐c]pyrazole derivative 15.  相似文献   

18.
19.
Abstract

In this study, we are introducing a method that can effectively stabilize antioxidants in water‐in‐oil‐in‐water (W/O/W) double emulsions. Preliminarily, stable W/O/W double emulsions were produced by manipulating the characteristics of internal aqueous phase via two‐stage emulsification, resulting consequently in the formation of fine internal water droplets in the dispersed oil droplets. From conductivity measurements that can determine the elution amount of internal aqueous phase, it was confirmed that the double emulsion stability could be improved by treating the internal aqueous phase with a hydroxypropyl‐beta‐cyclodextrin. In this study, kojic acid, 5‐hydroxy‐2‐(hydroxymethyl)‐4‐pyrone was selected as a model antioxidant. The stabilization of kojic acid was attempted by locating it in the internal water droplets of the stable W/O/W double emulsions. The stability of kojic acid in the double emulsion system could be maintained at 90% for 10 weeks at high temperature. We believe that these stable W/O/W double emulsions could be used meaningfully as a carrier for many unstable antioxidants.  相似文献   

20.
4-Methyl-3,4-epithiotetrahydropyran was synthesized by the recyclization of 4-methyl-3,4-epoxytetrahydropyran by the action of thiourea. The product reacts with -amino acids in an alkaline medium with regioselective opening of the thiirane ring at the least substituted carbon atom.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号