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1.
An efficient and convenient preparation of fullerenols was described. With polyethylene glycol (PEG) 400 as catalyst, fullerenols were conveniently synthesized via the direct reaction of fullerene with aqueous NaOH. By control of reaction conditions, either water-soluble C60 fullerenol or water-insoluble C60 fullerenol could be obtained selectively.  相似文献   

2.
A general and practical chemical route to the synthesis of N‐sulfonylimines using montmorillonite K‐10 as the catalyst is described. This method provides several advantages such as operational simplicity, short reaction time, using of inexpensive materials, noncorrosivity, lack of pollution, and high yields.  相似文献   

3.
A very short, high‐yielding, one‐pot procedure has been developed for the preparation of half‐protected cyclobutane‐1,2‐dione. This compound is much more stable than cyclobutane‐1,2‐dione itself and allowed further transformation to give diprotected cyclobutanetrione equivalents.  相似文献   

4.
A simple and efficient one‐pot method is described for the synthesis of phosphoramidates/phosphates in excellent yields from dialkylphosphites and trichloroisocyanuric acid in acetonitrile and subsequent treatment with dialkyl amines/alcohols. The procedure is operationally simple, has reduced reaction times, and uses a one‐pot procedure.  相似文献   

5.
In the Presence of NaBH4/BF3,allyl ethers underwent deallylation to the corresponding alcohols or phenols in good yield and high reaction rate.  相似文献   

6.
Chiral 3‐methanesulfonyl‐1‐Boc‐pyrrolidine and piperidine were reacted with sodium phenolates, resulting in a mixture of displacement and elimination products. Following carbamate deprotection and pH adjustment, the 3‐pyrroline and tetrahydropyridine by‐products resulting from elimination were easily removed through aqueous partitioning and/or concentration. Although the pyrrolidines were formed with a high degree of optical purity, slight racemization was observed for the piperidine case because elevated temperatures were required to effect displacement.  相似文献   

7.
A Convenient and Efficient Procedure for Oxime Ethers   总被引:1,自引:0,他引:1  
In connection with our asymmetric reduction research, we are of interest to synthesize ketoxime ethers because they give good enantioselectivty in the reduction system of Lewis acid-NaBH4-Ligand1. In the literature the oxime ethers were made under anhydrous conditions using strong base such as NaH or sodium alkoxides to realize the substitution reaction between alkyl halide and oxime2. The reaction has also been performed under PTC conditions3. There were cases where the yields were low…  相似文献   

8.
Chromone-2-carboxylates are widely used for the pharmacological activity of several of its derivatives1. The general synthesis of such chromone derivates includes two steps (Scheme 1): a Claison condensation of dialkyl oxalate with 2-hydroxyacetophenones to achieve alkyl 3-(2-hydroxyphenyl)-3-oxopropanoates in the presence of NaH, NaOEt, or NaOMe; cyclodehydration of the alkyl 3-(2-hydroxyaryl)-3-oxopropanoates to obtain chromones under acid condition. The total yield of the two steps is q…  相似文献   

9.
A convenient method for the preparation of peraza crown ethers in a one‐pot synthesis in the presence of KF/Al2O3 is presented.  相似文献   

10.
Acetophenone oxime and benzaldehyde oxime were converted to oxime ethers in the presence of alkyl halide or methyl sulfate and KOH in aqueous DMSO in 5 to 70 min. The yields of oxime ethers were 70-96%.  相似文献   

11.
Several methodologies to produce α-terpinyl chloride from “hydrochlorination” of limonene were studied and the best results were obtained by reaction with 0.5 mol equiv. SOCl2 in SiO2 / CH2Cl2. Using this methodology (R)- and (S)-α-terpinyl chloride can easily be prepared in good yields from (R)- and (S)-limonene, respectively.  相似文献   

12.
Jun Cheng  Naiyun Xiu  Xiangbin Li 《合成通讯》2013,43(18):2395-2399
The oxidative cyclization of 2,3‐diaminobenzoic acid and aromatic aldehydes to give 2‐aryl‐1H‐benzimidazole‐4‐carboxylic acids is reported. Moreover, three methods were compared in different perspectives from experimental manipulation to yield.  相似文献   

13.
The title chroman is useful in synthesis and as a water‐soluble analog of γ‐tocopherol, a member of the vitamin E family. This new synthesis of γ‐trolox proceeds via selective aromatic demethylation of Trolox, the more easily available 2,5,7,8‐tetramethyl homolog compound. This route is shorter than the previous synthesis, avoids the use of cyanide and methoxybutadiene, and requires no chromatography.  相似文献   

14.
7,8‐Dimethoxytetralin‐2‐one (1), an important intermediate for the synthesis of compounds possessing biological activity, was synthesized by simple reaction steps from commercially available starting materials.  相似文献   

15.
The controlled syntheses of mono‐ and bis‐acetylpyridine from the same starting material (2,6‐dimethylpyridine) are reported, including the asymmetrical compound 2‐acetyl‐6‐carbethoxypyridine, which has not before been reported. The influences of the amount of catalyst EtONa and the reaction conditions to the final products are also explored. A modification of the reported preparation for the 2,6‐dipicolinic acid, 2,6‐dicarbethoxypyridine and 2,6‐diacetylpyridine with higher purity and improved yields is provided here, and the physical and spectral properties of these products are identical to those reported in the literature.  相似文献   

16.
A simple and efficient preparation of a number of hybrid linear‐branched PEG esters are described. The polymers are generated by direct coupling of PEG–carboxylic acids and a variety of pentaerythritol ethoxylates using carbon tetrabromide catalyst.  相似文献   

17.
HubeiNaturalScienceFoundationforfinancialsupportChap-cyethy-S-allylthiOlwioSPhates(2a-j)havePOtenhalbiologicalachvihes.Inl983,Y.TamaruandZYoshidarePOrtedPallatuxn(o)catalyZedthiono-ffooloallylicrearr~mentOfcrallylphoSPhoro-andphoSPhonotheonaes,andaiSOreinvestigaedthennalrearrangementOfa-andy-methallyldiethyphOSPhorothionaesinrelallontotheregioselectivityObserVedinthePalladium(O)catalySisl'].InourPreviousStUdy,Hg(II)catalghcandthermalffoono-ffoolorearrangmentOfcrPrOPargylcreqlp…  相似文献   

18.
Pure mono-3-O-phenylcarbamoyl-β-CD was prepared in good yield via a silyl intermediate. This product was found to be an efficient chiral selector in the separation of chiral drug isomers by capillary electrophoresis.  相似文献   

19.

An efficient preparation of benzylidene acetals of carbohydrate derivatives catalyzed by iodine has been developed. Yields were excellent in every case.  相似文献   

20.
Summary. In view of finding new 5-HT6 receptor ligands various -acetamido substituted tryptamine and N,N-dimethyltryptamine derivatives were synthesized from a common intermediate. A trimolecular condensation between indole, Meldrums acid and N-phthalimidoacetaldehyde followed by careful deprotection and functional group manipulations were proposed for this purpose.Present address: GEVSM, UMR 7565 CNRS-UHP, Faculté de Pharmacie, F-54001 Nancy Cedex, FrancePresent address: University of Global and National Economy, Studentski Grad Christo Botev, BG-1700 Sofia, Bulgaria  相似文献   

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