共查询到20条相似文献,搜索用时 15 毫秒
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Kumkum KumariDushyant Singh Raghuvanshi Viatcheslav JouikovKrishna Nand Singh 《Tetrahedron letters》2012,53(9):1130-1133
An efficient, rapid, and green synthesis of functionalized pyrazoles has been accomplished under solvent-free conditions by the reaction of phenyl hydrazine, aldehydes and ethyl acetoacetate. This approach exploits the synthetic potential of microwave irradiation and scandium triflate combination and offers many advantages such as excellent product yields, shorter reaction time, easy isolation of products, and environmentally benign reaction conditions. 相似文献
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Srivari Chandrasekhar Vidyavathi Patro Lahu N. Chavan Rambabu Chegondi René Grée 《Tetrahedron letters》2014
An efficient and eco-friendly method for the synthesis of substituted pyrroles has been developed via ruthenium-catalyzed multicomponent reaction of ketone, amine, and ethylene glycol in PEG-400 as solvent medium without using any external ligand. The catalytic system and solvent can be recycled with the same, as well as different, ketones with minimum loss of Ru-catalyst activity. 相似文献
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An efficient ‘one-pot’ synthesis of the title compounds based on a multicomponent domino reaction between imines and 3-nitro-1-propanol methanesulfonate has been developed. 相似文献
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A small library of benzoxazine-fused isoquinolines has been synthesized under microwave irradiation (MW) via CuI-catalyzed domino reactions of o-alkynyl aldehydes and amines having embedded nucleophiles. This strategy offers a operationally simple, environmentally acceptable route to synthesize benzoxazine-fused isoquinolines in moderate to good yields. All new compounds were characterized by 1H NMR, 13C NMR, infrared, and high-resolution mass spectrometry techniques. 相似文献
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《Green Chemistry Letters and Reviews》2013,6(3):222-227
Sulfonyl azides have efficiently been synthesized via a convenient and environmentally benign procedure, in which sulfonyl chlorides undergo nucleophilic substitution reaction with sodium azide in PEG-400 under mild conditions. The sulfonyl azides were obtained in 84–97% isolated yields. 相似文献
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Gurusamy Harichandran Savarimuthu David Amalraj Ponnusamy Shanmugam 《Journal of Saudi Chemical Society》2018,22(2):208-217
A one-pot Amberlite IRA-400 Cl resin catalyzed the in-situ generation of imines from various aldehydes and primary amines followed by reduction with sodium borohydride affording corresponding secondary amines. The secondary amines thus obtained were utilized for the IRA-400 Cl resin catalyzed multicomponent synthesis of 3-aminoalkylated indoles using a number of aldehydes and indole. Mild condition, easy work-up, and environmentally benign nature of the synthetic strategy make it both practical and attractive. 相似文献
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Fengtian Wu 《应用有机金属化学》2020,34(12):e5975
N-containing heterocyclic compounds are one of the most important motifs prevalent in various bioactive natural products and pharmaceuticals. Given the significance of N-containing heterocyclic compounds, various synthetic strategies have been developed. Copper/ligand (abbreviated as [CuL])-catalyzed cascade reaction is a powerful and efficient tool for the construction of N-containing heterocyclic compounds. L-proline is one universal ligand and has been utilized in the copper-catalyzed reactions. In this review, copper/L-proline-catalyzed tandem reaction to synthesize the five- and six-membered compounds is emphatically introduced. By comparing the yields in the presence and absence of the ligand, the importance of L-proline is recorded. Moreover, the function of L-proline is expounded on the basis of the reaction mechanism from original article. 相似文献
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Sandra Jiménez-Alonso Haydee Chávez Ana Estévez-Braun Ángel G. Ravelo Gabriela Feresin 《Tetrahedron》2008,64(37):8938-8942
The synthesis of novel pyrano embelin derivatives has been achieved through domino Knoevenagel hetero Diels-Alder reactions of embelin (1) with paraformaldehyde and electron rich alkenes. This synthetic approach is highly efficient when microwave irradiation is used. 相似文献
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Silica gel-supported polyphosphoric acid(PPA-SiO2) was found to be an efficient catalyst for the one-pot four-component Hantzsch condensation reaction of aryl aldehydes,dimedone,ethyl acetoacetate and ammonium acetate to afford the corresponding polyhydroquinoline derivatives in high yields.The main advantages of the present approach are short reaction times,clean reaction profiles,simple experimental and workup procedures. 相似文献
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Lingaiah Nagarapu Raghu MallepalliLingappa Yeramanchi Rajashaker Bantu 《Tetrahedron letters》2011,52(26):3401-3404
Polyethylene glycol (PEG) was found to be an inexpensive non-toxic and effective medium for the one-pot synthesis of highly functionalized pyrroles. Utilizing this protocol various pyrrole derivatives were synthesized in excellent yields. Environmental acceptability, low cost, high yields, and recyclability of the PEG are the important features of this protocol. 相似文献
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A simple and convenient method towards the synthesis of highly diversified chromenopyrazole/indoline frameworks in excellent yields via iodine promoted triple domino reaction involving Michael addition followed by intramolecular cyclization and dehydrogenation sequence has been described for the first time. 相似文献
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Structurally diverse benzothiazolylquinoline-2,5-diones and their spiro analogues have been synthesized by an environmentally benign efficient and convenient synthetic method involving sulfamic acid catalyzed one-pot four-component reaction of Meldrum acid, 2-aminobenzothiazoles, dimedone, and isatin/carbonyl compound. 相似文献
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Hui Jian Qiang Wang Wei-Hua Wang Zhi-Juan Li Cheng-Zhi Gu Bin Dai Lin He 《Tetrahedron》2018,74(23):2876-2883
Diverse functionalized thioethers were efficiently synthesized through the multicomponent reaction of benzynes, cyclic thioethers and different nucleophiles. Both inorganic salts (KF, KCl, KBr, and KSCN) and silylated reagents (TMSCN, TMSN3, TMSCl) can be utilized as efficient nucleophiles for the reaction. 相似文献
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A one-pot direct regioselective iodination of Fischer-Borsche product using periodic acid in PEG-400
Monica H. Ghom Mahavir S. Naykode Vivek T. Humne Pradeep D. Lokhande 《Tetrahedron letters》2019,60(15):1029-1031
A metal-free and greener approach for the one-pot direct iodination and dehydrogenation of dihydrobenzo[a]carbazoles has been developed using periodic acid in polyethylene glycol-400 (PEG-400) under mild condition. This method has been proven to be tolerate to a broad range of functional groups, with good to excellent yields include metal-free inexpensive catalyst, easy work-up, benign reaction condition and high regioselectivity. The solvent has been successfully recycled up to 5 times without any loss of activity in an aqueous medium. 相似文献
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An efficient non-ionic surfactant catalyzed multicomponent synthesis of novel benzylamino coumarin derivatives has been developed from secondary amines, aromatic aldehyde, and 4-hydroxy coumarin via Mannich type reaction in aqueous media. In this Mannich type reaction, surfactant forms stable colloidal medium to stabilize iminium ion which undergoes nucleophilic addition of 4-hydroxy coumarin to give benzylamino coumarin in very good yields. 相似文献
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Akula Raghunadh Suresh Babu Meruva Ramamohan Mekala K. Raghavendra Rao Thalishetti Krishna R. Gangadhara Chary L. Vaikunta Rao U.K. Syam Kumar 《Tetrahedron letters》2014
An efficient synthesis of unsymmetrically substituted 1,3-pyrazole derivatives has been developed via three-component coupling reaction involving 3-(dimethylamino)-1-phenylprop-2-en-1-one, hydrazine, and aryl halides in one pot process exhibiting high regioselectivity. The pyrazole synthesis proceeds via a sequential series of reactions such as Michael addition, heterocyclization, dehydration, and Ullmann cross-coupling. 相似文献
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Chanikan Duangjan Vatcharin Rukachaisirikul Saowanit Saithong Juthanat Kaeobamrung 《Tetrahedron letters》2018,59(39):3537-3540
Quinazolinediones were obtained from 2-iodobenzoic acids and carbodiimide derivatives under mild reaction conditions via a copper-catalyzed domino reaction. The absence of an external base was essential to avoid the generation of amide by-products. Both alkyl- and aryl-substituted carbodiimides gave the corresponding quinazolinediones. However, the use of aryl-substituted carbodiimides resulted in low yields due to an undesired elimination process. 相似文献