共查询到20条相似文献,搜索用时 15 毫秒
1.
An efficient method for the preparation of 2‐substituted 4‐aryl‐4,5‐dihydro‐3,1‐benzoxazepine derivatives under mild conditions has been developed. The reaction of 2‐(2‐aminophenyl)ethanols 1 with acid chlorides in the presence of excess Et3N in THF at room temperature gave the corresponding N‐acylated intermediates 2 , which were dehydrated by treatment with POCl3 to give 2‐substituted 4‐aryl‐4,5‐dihydro‐3,1‐benzoxazepines 3 in a one‐pot reaction. 相似文献
2.
A one‐pot synthesis of 2‐imino‐4‐methylidene‐1,3‐dithiolanes via a three‐component reaction of propargyl bromide (=3‐bromoprop‐1‐yne), primary amines, and carbon disulfide (CS2) is described. 相似文献
3.
Guoping Cai Xiaoliang Xu Zhifang Li Ping Lu William P. Weber 《Journal of heterocyclic chemistry》2002,39(6):1271-1272
2‐Aryl‐2,3‐dihydro‐4(lH)‐quinazolines have been prepared in a one‐pot synthesis by samarium idoide (SmI2) promoted reaction of o‐nitrobenzamide and aldehydes. 相似文献
4.
Kazuhiro Kobayashi Natsuki Konishi Teruhiko Suzuki Kazuhiro Nakagawa 《Helvetica chimica acta》2013,96(8):1452-1456
An efficient one‐pot synthesis of novel heterocyclic derivatives, 2‐aryl‐1,4‐oxathiino[2,3‐b]quinoxalines or ‐pyrazines 5 , via the reaction of 2,3‐dichloroquinoxaline or ‐pyrazine with Na2S?9 H2O, and subsequent treatment of the resulting 2‐chloro‐3‐sodiosulfanylquinoxaline or ‐pyrazine 2 with 1‐aryl‐2‐bromo‐1‐alkanones and then NaH under mild conditions is described. 相似文献
5.
One‐Pot Synthesis of 3‐Acetyl‐2‐aryl‐3,4‐dihydroquinazolines from N‐[2‐(Azidomethyl)phenyl]benzamides Utilizing Intramolecular Aza‐Wittig Reaction 下载免费PDF全文
Kazuhiro Kobayashi Naoki Matsumoto Mika Nagashima Hiroki Inouchi 《Helvetica chimica acta》2015,98(2):184-189
A new and convenient method for the preparation of 3,4‐dihydroquinazolines 5 with aryl and Ac groups at C(2) and N(3), respectively, has been developed. The key sequence is the formation of aza‐phosphorane intermediates by the reaction of N‐[2‐(azidomethyl)phenyl]benzamides 1 with Ph3P, followed by intramolecular aza‐Wittig reaction and 3‐acetylation, which can be conducted in one‐pot. 相似文献
6.
Rajasekar Perumal Balaji Bathrinarayanan Majid Ghashang Syed Sheik Mansoor 《Journal of heterocyclic chemistry》2019,56(3):947-955
Chitosan sulfonic acid (CS–SO3H), a biodegradable green catalyst, was found to be an impressive system for one‐pot four‐component reaction of different aromatic aldehydes, 3‐acetylcoumarin, dimedone, and ammonium acetate leading to 7,7‐dimethyl‐2‐(2‐oxo‐2H‐chromen‐3‐yl)‐4‐aryl‐7,8‐dihydroquinolin‐5(6H)‐one under solvent‐free condition. This methodology produces diverse superiorities such as operational simplicity, short reaction time, and high yield. Further, the catalyst can be reused for four times without any noticeable decrease in the catalytic activity. 相似文献
7.
《Journal of heterocyclic chemistry》2017,54(6):3071-3076
An efficient method for the synthesis of N‐alkylated 2‐(4‐substituted‐1H‐1,2,3‐triazol‐1‐yl)‐1H‐indole‐3‐carbaldehyde has been developed starting from oxindole and indole using Huisgen's 1,3‐dipolar cycloaddition reaction of organic azides to alkynes. The effect of catalysts and solvent on these reactions has been investigated. Among all these conditions, while using CuSO4·5H2O, DMF was found to be the best system for this reaction. It could also be prepared in a one‐pot three‐component manner by treating equimolar quantities of halides, azides, and alkynes. The Huisgen's 1,3‐dipolar cycloaddition reaction was performed using CuSO4·5H2O in DMF with easy work‐up procedure. 相似文献
8.
Han‐Xun Wei Jiali Hu RichardL. Jasoni Guigen Li PaulW. Par 《Helvetica chimica acta》2004,87(9):2359-2363
The efficient and highly stereoselective syntheses of a variety of (Z)‐configured, substituted α‐(hydroxymethyl) ‐ β‐iodo‐acrylates from prop‐2‐ynoate and various aldehydes was achieved. The synthetic protocol involves a simple one‐pot coupling reaction under mild conditions, promoted by MgI2, which serves both as a Lewis acid and iodine source for a Baylis? Hillman‐type reaction. All adducts were generated in good‐to‐excellent yields, the (Z)‐isomers being formed in high selectivity (>98%). The conversion of methyl prop‐2‐ynoate into an active ‘β‐iodo allenolate’ intermediate, which then nucleophilically attacks an aldehyde, is proposed as a plausible reaction mechanism. 相似文献
9.
Alireza Hasaninejad Nooshin Golzar Abdolkarim Zare 《Journal of heterocyclic chemistry》2013,50(3):608-614
A one‐pot, four‐component reaction for the efficient synthesis of novel spiro[indeno[2,1‐b]quinoxaline‐11,4′‐pyran]‐2′‐amines by using InCl3 is described. The syntheses are achieved by reacting ninhydrin with 1,2‐diaminobenzenes to give indenoquinoxalines, which are trapped in situ by alkyl malonates and various α‐methylencarbonyl compounds through cyclization, providing multifunctionalized spiro‐substituted indeno[2,1‐b]quinoxaline‐11,4′‐pyran‐2′‐amines. 相似文献
10.
Subhash C. Jain Aparna Bharadvaja Rohtash Kumar Deepti Agarwal William Errington 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):592-593
The facile one‐pot synthesis of the title compound, C25H21N3O2S, is described. The six‐membered 1,3‐diaza ring is puckered with an axial phenyl group in the 2‐position. Intermolecular hydrogen bonding between hydroxyl and ketonic O atoms produces infinite one‐dimensional chains in the a direction. 相似文献
11.
One‐Pot Synthesis of 2‐Oxazolines from Ethyl α‐Cyanocinnamate Derivatives with N‐Bromoacetamide 下载免费PDF全文
Zhanguo Chen Hua Wen Wenli Li Jimei Zhou Junli Hu Wei Xia 《Journal of heterocyclic chemistry》2014,51(3):794-802
An efficient method for the one‐pot synthesis of 2‐oxazolines from ethyl α‐cyanocinnamate derivatives with N‐bromoacetamide in the presence of K3PO4 has been developed. The reaction performed smoothly and cleanly to give 2‐oxazolines in good to excellent yields (up to 98%) within 4.5 h in acetone at room temperature without protection of inert gases. A total of 13 examples have been investigated. A possible nucleophilic addition reaction mechanism is proposed. 相似文献
12.
Abdolali Alizadeh Zohreh Noaparast Hamideh Sabahno Nasrin Zohreh 《Helvetica chimica acta》2010,93(7):1401-1406
Synthesis and characterization of bis[2‐(arylimino)‐1,3‐thiazolidin‐4‐ones] are described. The one‐pot, pseudo‐five‐component reaction of an aliphatic diamine, isothiocyanatobenzene, and dialkyl but‐2‐ynedioate at room temperature in anhydrous CH2Cl2 gives the title compound in relatively high yield. Under the same conditions, aromatic 1,2‐diamines yield 2‐(arylimino)‐N‐(enaminoaryl)‐1,3‐thiazolidin‐4‐ones in a pseudo‐four‐component reaction. Their structures were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this type of cyclization is proposed (Scheme 3). 相似文献
13.
Gowravaram Sabitha KusumaB. Reddy Rangavajjula Srinivas JilluS. Yadav 《Helvetica chimica acta》2005,88(11):2996-2999
A novel Biginelli‐like cyclocondensation reaction is efficiently catalyzed by iodotrimethylsilane (Me3SiI) in MeCN. The reaction proceeds at room temperature by a three‐component one‐pot condensation of ketones with aldehydes and urea to afford 5‐unsubstituted 3,4‐dihydropyrimidin‐2(1H)‐ones in good yields (Scheme 1 and Table). 相似文献
14.
Synthesis of Novel α‐(Acyloxy)‐α‐(quinolin‐4‐yl)acetamides by a Three‐Component Reaction between an Isocyanide,Quinoline‐4‐carbaldehyde,and Arenecarboxylic Acids 下载免费PDF全文
Jafar Taran Ali Ramazani Sang Woo Joo Katarzyna Ślepokura Tadeusz Lis 《Helvetica chimica acta》2014,97(8):1088-1096
Novel α‐(acyloxy)‐α‐(quinolin‐4‐yl)acetamides were synthesized by the Passerini three‐component reaction between an isocyanide, quinoline‐4‐carbaldehyde, and arenecarboxylic acids in H2O. The reactions were carried out in one pot at room temperature with quantitative yields. 相似文献
15.
《Journal of heterocyclic chemistry》2017,54(4):2471-2482
An eco‐friendly method has been developed for the synthesis of 2‐amino‐4‐(9H‐carbazole‐3‐yl)thiophene‐3‐carbonitriles from preliminary carbazole ( 1 ) through an intermediate of 2‐(1‐(9H‐carbazole‐3‐yl)ethylidene)malononitriles using the Knoevenagel condensation followed by the Gewald reaction. On the other hand, the target compounds could also be prepared in a one‐pot three‐component manner by treating equimolar quantities of 1‐(9H‐carbazole‐3‐yl)ethanone ( 3 ), malononitrile, and elemental sulfur. The merits of this preparation are mild reaction conditions. The Gewald reaction is executed with inorganic base NaHCO3 (H2O) in tetrahydrofuran, easy work‐up procedure with good yields. 相似文献
16.
Elmira Ghabraie Morteza Bararjanian Saeed Balalaie Frank Rominger Hamid Reza Bijanzadeh 《Helvetica chimica acta》2011,94(8):1440-1447
The Michael‐type addition of a 4‐hydroxycoumarin (=4‐hydroxy‐2H‐1‐benzopyran‐2‐one) 1 to a β‐nitrostyrene (=(2‐nitroethenyl)benzene) 2 in the presence of AcONH4 leads to substituted (3E)‐3‐[amino(aryl)methylidene]chroman‐2,4‐diones (=(3E)‐3‐[amino(aryl)methylene]‐2H‐1‐benzopyran‐2,4(3H)‐diones) 4 (Table 1). High yields, short reaction time, and easy workup are advantages of this novel one‐pot three‐component reaction. 相似文献
17.
Xiao Wang Guangzhou Lu Fulin Yan Weiwei Ma Liqiang Wu 《Journal of heterocyclic chemistry》2011,48(6):1379-1382
A new, one‐pot, simple thermally efficient and solvent‐free method for the preparation of 7‐alkyl‐6H,7H‐naphtho[1′,2′:5,6]pyrano[3,2‐c]chromen‐6‐ones by condensation of β‐naphthol, aromatic aldehydes, and 4‐hydroxycoumarin using Zr(HSO4)4 as a safe and efficient catalyst is described. This method has the advantages of high yields, a cleaner reaction, simple methodology, short reaction times, easy workup, and greener conditions. J. Heterocyclic Chem., (2011). 相似文献
18.
Green Biginelli‐type Reaction: Solvent‐free Synthesis of 5‐unsubstituted 3,4‐dihydropyrimdin‐2(1H)‐ones 下载免费PDF全文
The Biginelli‐type compounds, 5‐unsubstituted 3,4‐dihydropyrimdin‐2(1H)‐ones were synthesized by a one‐pot three‐component condensation of aromatic aldehydes, aromatic ketones and urea in the presence of SnCl4 · 5H2O under solvent‐free conditions. The advantages of this method are short reaction time (4–10 min), excellent yields (74–97%), inexpensive catalyst and solvent‐free conditions. A plausible mechanism was proposed. 相似文献
19.
A general and practical procedure for the syntheses of 3,4-di-hydropyrimidine-2(1H)-thiones by a one-pot condensation of aldehyde,β-ketoester or β-diketone and thiourea using La(OTf)3 as the catalyst is described.Mild reaction conditions,excellent yields as well as the environmentally friendly character of La(OTf)3 make it an important alternative to the classic acid-catalyzed Biginelli‘s reaction. 相似文献
20.
An Efficient Synthesis of 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐6‐methyl‐4‐(2‐oxo‐2‐phenylethoxy)‐3,4‐dihydro‐2H‐pyran‐2‐one Derivatives via Multi‐Component Approach 下载免费PDF全文
An easy, highly efficient and a new convenient one‐pot, two‐step approach to the synthesis of 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐6‐methyl‐4‐(2‐oxo‐2‐phenylethoxy)‐3,4‐dihydro‐2H‐pyran‐2‐one is described. These compounds were synthesized from 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐4‐hydroxy‐6‐methyl‐3,4‐dihydro‐2H‐pyran‐2‐one and α‐bromoketones in good yields. The compounds 4 were synthesized by a multi‐component reaction between 1 , 2 , and 3 and the prominent features of this protocol are mild reaction conditions, operation simplicity, and good to high yields of products. 相似文献