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1.
Parthasarathy Gandeepan Julian Koeller Korkit Korvorapun Jens Mohr Lutz Ackermann 《Angewandte Chemie (International ed. in English)》2019,58(29):9820-9825
Visible‐light‐induced ruthenium catalysis has enabled remote C?H alkylations with excellent levels of position control under exceedingly mild conditions at room temperature. The metallaphotocatalysis occurred under exogenous‐photosensitizer‐free conditions and features an ample substrate scope. The robust nature of the photo‐induced mild meta‐C?H functionalization is reflected by the broad functional group tolerance, and the reaction can be carried out in an operationally simple manner, setting the stage for challenging secondary and tertiary meta‐C?H alkylations by ruthenaphotoredox catalysis. 相似文献
2.
An efficient and simple procedure was developed for the green synthesis of various 2‐aryl‐1‐ben‐zylated‐1H‐benzimidazoles in high yields by condensation of o‐phenylenediamine with aldehydes with P2O5/SiO2 as catalyst under solvent‐free and ambient conditions. 相似文献
3.
Room‐Temperature ortho‐Alkoxylation and ‐Halogenation of N‐Tosylbenzamides by Using Palladium(II)‐Catalyzed CH Activation 下载免费PDF全文
Dr. Florent Péron Dr. Christine Fossey Prof. Dr. Jana Sopkova‐de Oliveira Santos Dr. Thomas Cailly Prof. Dr. Frédéric Fabis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(24):7507-7513
The N‐tosylcarboxamide group can direct the room‐temperature palladium‐catalyzed C?H alkoxylation and halogenation of substituted arenes in a simple and mild procedure. The room‐temperature stoichiometric cyclopalladation of N‐tosylbenzamide was first studied, and the ability of the palladacycle to react with oxidants to form C?X and C?O bonds under mild conditions was demonstrated. The reaction conditions were then adapted to promote room‐temperature ortho‐alkoxylations and ortho‐halogenations of N‐tosylbenzamides using palladium as catalyst. The scope and limitation of both alkoxylations and halogenations was studied and the subsequent functional transformation of the N‐tosylcarboxamide group through nucleophilic additions was evaluated. This methodology offers a simple and mild route to diversely functionalized arenes. 相似文献
4.
Magnetic Nanoparticle Supported Ionic Liquid Assisted Green Synthesis of Pyrazolopyranopyrimidines and 1,6‐diamino‐2‐oxo‐1,2,3,4‐tetrahydropyridine‐3,5‐ dicarbonitriles 下载免费PDF全文
A simple and eco‐friendly green protocol was used for synthesis of pyrazolopyranopyrimidines via four‐component reaction of hydrazine hydrate, ethyl acetoacetate, barbituric acid or dimethyl barbituric acid, and aromatic aldehydes under thermal and solvent‐free conditions in the presence of magnetic nanoparticle supported silica bonded n‐propyl‐4‐aza‐1‐azoniabicyclo[2.2.2]octane chloride (MNPs@DABCO+Cl?) as an efficient, recyclable heterogeneous catalyst. MNPs@DABCO+Cl? also catalyzed the synthesis of 1,6‐diamino‐2‐oxo‐1,2,3,4‐tetrahydropyridine‐3,5‐dicarbonitrile derivatives by four‐component reaction of hydrazine hydrate, malononitrile, ethyl cyanoacetate and ketones under thermal and solvent‐free conditions at 80 °C. These methods are practical and offer many advantages, such as high yields, short reaction times, and simple work‐up. 相似文献
5.
《Journal of heterocyclic chemistry》2017,54(1):305-312
A simple, efficient, and eco‐friendly procedure has been developed for the synthesis of bis(4H‐chromene‐3‐carbonitrile) derivatives using chitosan as catalyst under microwave‐assisted reaction conditions. For the sake of comparison, the reaction was also carried out under conventional heating in the presence of each of chitosan and piperidine as basic catalysts. 相似文献
6.
《Journal of heterocyclic chemistry》2018,55(6):1499-1503
A convenient eco‐friendly one‐pot synthesis of 14‐aryl‐14H‐dibenzo [a, j] xanthenes were developed by the condensation of aromatic aldehydes and β‐naphthol with BTADCI (Benzyltrimethylammonium dichloroiodate) as catalyst under solvent free conditions and microwave irradiation with much more rate accelerations and afford very good yields. Developed protocols involve mild reaction conditions, simple isolation of derivatives with inexpensive reagents. 相似文献
7.
Dr. Raju Ghosh Elin Stridfeldt Prof. Berit Olofsson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8888-8892
Ethyl acetohydroxamate was efficiently arylated with diaryliodonium salts at room temperature under transition‐metal‐free conditions. The obtained O‐arylated products were reacted in situ with ketones under acidic conditions to yield substituted benzo[b]furans through oxime formation, [3,3]‐rearrangement, and cyclization in a fast and operationally simple one‐pot fashion without using excess reagents. Alternatively, the O‐arylated products could be isolated or transformed in situ to aryloxyamines or O‐arylaldoximes. The methodology was applied to the synthesis of Stemofuran A and the formal syntheses of Coumestan, Eupomatenoid 6, and (+)‐machaeriol B. 相似文献
8.
A simple, general and efficient method has been developed for synthesis of various β-enamino ketones and esters by reacting β-dicarbonyl compounds with amines using a catalytic amount of L-proline at room temperature under solvent-free conditions in excellent yields. 相似文献
9.
Mehdi Adib Samira Ansari Long‐Guan Zhu Mehdi Rahimi‐Nasrabadi 《Helvetica chimica acta》2013,96(4):675-681
A simple synthesis of 2‐hydrazinylidene‐3‐hydroxy‐4H‐furo[3,2‐c]pyran‐4‐ones is described. A mixture of (isocyanoimino)(triphenyl)phosphorane, an aromatic aldehyde, and dehydroacetic acid (=3‐acetyl‐2‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one) undergo a 1 : 1 : 1 addition reaction under mild conditions to afford the title compounds in excellent yields. 相似文献
10.
Four‐Component,One‐Pot Synthesis of 1,4‐Disubstituted 1,2,3‐Triazoles Bearing 1‐(2‐Phenylselenocyclohexyl) Group 下载免费PDF全文
Wusheng Sheng Shouri Sheng Jiangbo Zeng Zhenzhong Huang Mingzhong Cai 《Journal of heterocyclic chemistry》2014,51(Z1):E222-E226
An efficient, one‐pot, three‐step, regioselective synthesis of 4‐substituted 1‐(2‐phenylselenocyclohexyl)‐1,2,3‐triazoles, involving in situ generation of l‐azido‐2‐phenylselenocyclohexane has been developed via four‐component reaction of phenylselenenyl bromide, cyclohexene, sodium azide and terminal alkynes catalyzed by copper iodide in a mixture of DMF/THF (1:1) at room temperature under mild conditions with simple workup and good yields. 相似文献
11.
Lijiu Gao Honglou Ji Liangce Rong Dan Tang Yunyun Zha Yanhui Shi Shujiang Tu 《Journal of heterocyclic chemistry》2011,48(4):957-960
A simple, efficient and convenient one‐pot synthesis of 2,3‐dihydroquinazolin‐4(1H)‐one derivatives under solvent‐free and catalyst‐free conditions by the reaction of aromatic aldehydes, isatoic anhydride, and ammonium acetate was reported. The advantages of this protocol include short reaction time, mild reaction conditions, easy work‐up, high yields, and environmental friendliness. J. Heterocyclic Chem., (2011). 相似文献
12.
A simple and facile synthesis of 2H‐indazolo[2,1‐b]phthalazine‐1,6,11(13H)‐trione derivatives has been accomplished by a three‐component condensation reaction of dimedone, aromatic aldehydes and phthalhydrazide under solvent‐free conditions in the presence of wet cyanuric chloride as a catalyst. 相似文献
13.
Ultrasound‐Assisted Synthesis of 6‐Methyl‐1,2,3,4‐tetrahydro‐N‐aryl‐2‐oxo/thio‐4‐arylpyrimidine‐5‐carboxamides Catalyzed by Uranyl Nitrate Hexahydrate 下载免费PDF全文
An efficient and simple method developed for the synthesis of 6‐methyl‐1,2,3,4‐tetrahydro‐N‐aryl‐2‐oxo/thio‐4‐arylpyrimidine‐5‐carboxamide derivatives ( 4a‐o ) using UO2(NO3)2.6H2O catalyst under conventional and ultrasonic conditions. The ultrasound irradiation synthesis had shown several advantages such as milder conditions, shorter reaction times and higher yields. The structures of all the newly synthesized compounds have been confirmed by FT‐IR, 1H NMR, 13C NMR and mass spectra. 相似文献
14.
A simple and efficient procedure for the preparation of silica‐bonded propyl‐diethylene‐triamine‐N‐sulfamic acid (SPDTSA) by reaction of 3‐diethylenetriamine‐propylsilica (DTPS) and chlorosulfonic acid in chloroform is described. Silica‐bonded propyl‐diethylene‐triamine‐N‐sulfamic acid is employed as a recyclable catalyst for the synthesis of 1,1‐diacetates from aromatic aldehydes and acetic anhydride under mild and solvent‐free conditions at room temperature. Catalyst could be recycled for several times without any additional treatment. 相似文献
15.
Manoj B. Gawande Sharad N. Shelke Paula S. Branco Anuj Rathi Rajesh K. Pandey 《应用有机金属化学》2012,26(8):395-400
An environmentally benign method for O‐tert‐Boc protection of alcohols and phenols catalyzed by MgO–ZrO2 nanoparticles under solvent‐free conditions is described. A variety of phenols, alcohols (aliphatic and aromatic) were converted to corresponding O‐tert‐Boc products in good to excellent yield (50–95%). The present protocol is expedient, simple, and efficient under solvent‐free conditions. The MgO–ZrO2 Nps are easily prepared from inexpensive precursors, and are reusable, recyclable and chemoselective. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
16.
The hitherto unreported, highly functionalized 1H‐pyrazole‐3‐carboxylates 3 have been synthesized in good yields via a one‐pot three‐component domino reaction of phenylhydrazines, dialkyl acetylenedicarboxylates, and ninhydrin under mild conditions for the first time. No co‐catalyst or activator is required for this multicomponent reaction, and the reaction is, from an experimental point of view, simple to perform (Scheme 1). The structures of compounds 3 were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this type of cyclization/addition reaction is proposed (Scheme 2). 相似文献
17.
Ligand‐free CuTC‐catalyzed N‐arylation of amides,anilines and 4‐aminoantipyrine: synthesis of N‐arylacrylamides, 4‐amido‐N‐phenylbenzamides and 4‐amino(N‐phenyl)antipyrenes 下载免费PDF全文
N‐Arylation of amides and anilines with aryl iodides was efficiently catalyzed by copper thiophenecarboxylate under ligand‐free conditions with good to excellent yields. A variety of substituted aryl iodides, amides, anilines and 4‐aminoantipyrine were found to be applicable to the simple catalytic system. Furthermore, some practical, unique secondary amides, such as N‐arylacrylamides and 4‐amido‐N‐phenylbenzamides, and 4‐amino(N‐phenyl)antipyrenes, which are difficult to obtain by the classical methods, were prepared. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
18.
Runhong Jia Juhua Peng Bo Jiang Junyong Zhang Shu‐Jiang Tu 《Journal of heterocyclic chemistry》2015,52(1):193-196
A facile microwave‐assisted synthesis of pyrano[2,3‐d]pyrimidines derivatives is accomplished via reactions of 4‐arylmethylene‐2‐phenyloxazol‐5(4H)‐ones with pyrimidine‐4,6‐diol in ethylene glycol. The reaction is simple to perform and occurs under mild conditions with broad scope of applicability. 相似文献
19.
Sodium Formate‐Catalyzed One‐Pot Synthesis of Benzopyranopyrimidines and 4‐Thio‐substituted 4H‐Chromenes via Multicomponent Reaction at Room Temperature 下载免费PDF全文
A simple, straightforward and highly efficient multicomponent one‐pot synthesis of a series of pharmaceutically interesting benzopyranopyrimidine and 4H‐chromene derivatives has been developed on the basis of low‐cost and environment‐friendly sodium formate catalyst via tandem reactions of salicylic aldehydes, malononitrile, and cyclic secondary amines in ethanol at room temperature. Nature of nucleophile used in this reaction directs the course of the reaction; cyclic secondary amines result in the formation of benzopyrano[2,3‐d]pyrimidines, whereas thiophenol furnish corresponding 4‐thio‐subtituted 4H‐chromenes under the same reaction conditions. High atom‐economy, good yields, eco‐friendly, and mild reaction conditions are some of the important features of this protocol. 相似文献
20.
Jabbar Khalafy Nasser Etivand Ahmad Poursattar Marjani Neda Khalillou 《Journal of heterocyclic chemistry》2019,56(6):1857-1865
The one‐pot, three‐component, synthesis of a new series of 4‐hydroxy‐3‐(2‐arylimidazo[1,2‐a]pyridin‐3‐yl)quinolin‐2(1H)‐ones in the presence of DABCO as a catalyst has been achieved using aryl glyoxal monohydrates, quinoline‐2,4(1H,3H)‐dione, and 2‐aminopyridine in H2O/EtOH under reflux conditions. The cheapness of organocatalyst, simple workup, operational simplicity, regioselectivity, and high yields are some advantages of this protocol. 相似文献