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991.
M. Gopalakrishnan P. Sureshkumar V. Kanagarajan J. Thanusu Shanmugam Govindan Mahesh Reddy Ghanta 《合成通讯》2013,43(13):1923-1926
The p‐toluenesulphonic acid–catalyzed reaction between appropriate cresols and N‐methyl‐3‐phenyl‐3‐hydroxypropylamine in refluxing toluene resulted in the formation of o‐substituted phenol derivatives by an aromatic nucleophilic substitution reaction. 相似文献
992.
Richard J. Petroski 《合成通讯》2013,43(12):1727-1734
Aldehydes were conveniently protected as dimethylhydrazones by stirring a mixture of the aldehyde, N,N‐dimethylhydrazine, anhydrous magnesium sulfate, and dichloromethane at room temperature. Azeotropic removal of water, formed during the course of the reaction, was not required because anhydrous magnesium sulfate functions as a water scavenger. Deprotection of aldehyde dimethylhydrazones was accomplished by stirring a mixture of the aldehyde dimethylhydrazone and aqueous glyoxylic acid at room temperature. The reaction time for the preparation and deprotection of aldehyde dimethylhydrazones varied with the structure of the aldehyde. 相似文献
993.
A simple, efficient, and rapid method for high-yielding regioselective mono bromination of phenols and anilines has been achieved by treatment with N-bromasaccharin in the presence of a catalytic amount of tungstophosphoric acid. 相似文献
994.
Unlike other N-alkylsulfonanilides, indolinesulfonamides hydrolyze in 98% sulfuric acid. Recent work in this laboratory has shown that rearrangement can be achieved by using polyphosphoric acid. A series of substituted indolinesulfonamides has been prepared and rearranged to their corresponding indoline arylsulfones. 相似文献
995.
Matthew C. Davis 《合成通讯》2013,43(20):3519-3528
A rapid method to prepare 1,3,5‐triaminobenzene and its derivatives is the tris‐Curtius rearrangment of 1,3,5‐benzenetricarboxylic acid. The hazards associated with the acyl azide route are minimized by using 1,2‐dichloroethane as solvent. A second method that avoids acyl azide preparation uses diphenylphosphoryl azide to yield the tricarbamate in one step. 相似文献
996.
Atul C. Chaskar Arun A. Yadav Bhushan P. Langi Anita Murugappan Chetan Shah 《合成通讯》2013,43(19):2850-2856
Simple, efficient, and mild method for α-thiocyanation of ketones in presence of heteropolyacid has been developed. This methodology offered α-oxothiocyanates in good to excellent yields at room temperature in a highly selective manner. The catalyst could be efficiently recovered from the reaction and reused. 相似文献
997.
Aminosulfonic acid is an environmentally friendly catalyst. Grinding a mixture of aromatic aldehydes, barbituric acid, and H2NSO3H at room temperature (without any solvent) gave 5‐arylidene barbituric acid in high yields, providing a simple and efficient route to synthesis of these compounds. 相似文献
998.
A new and efficient method for the preparation of various phenyl esters has been achieved by a simple reaction of an acid with phenol in the presence of anhyd. ZnCl2 and a catalytic amount of AlCl3. This combined Lewis acid also catalyzes the selective phenyl esterification to different dioic acids and is very simple and high yielding. 相似文献
999.
Aryl amines react smoothly and efficiently with N-vinyl pyrrolidin-2-one in the presence of 4-nitro phthalic acid in acetonitrile to afford the corresponding 1-(2-methyl-1,2,3,4-tetrahydroquinolin-4-yl)pyrrolidin-2-ones in good yields. 相似文献
1000.
Abolfazl Olyaei Esmat Chehrehgosha Parashkuhi Saeed Raoufmoghaddam Mahdieh Sadeghpour 《合成通讯》2013,43(24):3609-3617
A series of novel N-heteroaryl α-arylglycines containing naphthol rings has been prepared by one-pot, three-component condensation reaction of glyoxalic acid, heteroaryl amines and naphthols in water at ambient temperature and under reflux conditions in moderate to high yields. The promising advantages such as removal of organic solvent, no need to catalyst, simplicity of the reaction procedure and easy product separation will be discussed in this article. 相似文献