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1.
Natarajan Arumugam Abdulrahman I. Almansour Raju Suresh Kumar Mohammad Altaf S.M. Mahalingam Govindasami Periyasami J. Carlos Menéndez Abdul Jaleel Mohammad Ali Al-Aizari 《Tetrahedron letters》2019,60(8):602-605
A series of structurally intriguing novel pyrrolo[3,2-c]quinolinone heterocyclic hybrids have been synthesized for the first time via a one-pot multicomponent domino reaction sequence that involves a 1,3-dipolar cycloaddition and two subsequent annulation steps. Baylis-Hillman adducts derived from various substituted benzaldehyde and methyl acrylate in presence of DABCO were used as a dipolarophiles, while the 1,3-dipole components were azomethine ylides, formed in situ from isatin derivatives and l-phenylalanine. The reaction generated five new bonds, three new rings and four contiguous stereocenters, which were created with full diastereomeric control. 相似文献
2.
Zihong Guo 《Tetrahedron letters》2004,45(5):919-921
An efficient synthesis of the core tricyclic structure (18) of vindoline has been achieved using the strategy, which features an intramolecular 1,3-dipolar cycloaddition of the azido dienone (12) to give aziridine (13) with complete region- and stereocontrol. 相似文献
3.
Jory Lietard 《Tetrahedron letters》2007,48(50):8795-8798
A new bromohexyl phosphoramidite was synthesized and used for the introduction of an azide function at the 5′-end of oligonucleotides after a treatment on solid support with sodium azide and sodium iodide. The corresponding 5′-azido oligonucleotide could be further used for ‘Click’ conjugation with alkyne derivatives or by Staudinger ligation. 相似文献
4.
Intramolecular click chemistry was utilized to effect synthesis of the benzofused, triazole ring systems. The trimethylsilyl group was found to impede the reaction progress, and therefore, conditions employing in situ removal of the TMS group coupled with microwave irradiation give the penultimate targets with good conversion. 相似文献
5.
Stefan Löber 《Tetrahedron》2004,60(39):8699-8702
1,3-Dipolar cycloaddition was employed for the synthesis of a highly practical REM resin. Exploiting this concept, the resulting triazolylmethyl acrylate (TMA) resin was used for an efficient parallel synthesis of tertiary amines by Michael addition, subsequent quarternization and cleavage by means of β-elimination. 相似文献
6.
A novel and metal free catalysis of synthesizing 5-substituted 1H-tetrazoles through 1,3-dipolar cycloaddition of boron-azides and nitriles is reported with broad substrate scope and excellent yields. 相似文献
7.
Highly regio- and stereoselective synthesis of tricyclic frameworks using Baylis-Hillman derivatives
Manickam Bakthadoss Nagappan Sivakumar Govindan Sivakumar Gandhi Murugan 《Tetrahedron letters》2008,49(5):820-823
A simple and convenient synthetic route for the synthesis of tricyclic chromeno[4,3-b]pyrrolidine frameworks using Baylis-Hillman bromides involving in situ formation of an imine, decarboxylation and a [3+2] cycloaddition sequence is described. 相似文献
8.
Stephen Michael RajeshBalasubramainan Devi Bala Subbu Perumal 《Tetrahedron letters》2012,53(40):5367-5371
A library of novel 1-methyl-4-arylpyrrolo-(spiro[2.2′]indan-1′,3′-dione)-spiro[3.3″]-1″-methyl/benzyl-5″-(arylmethylidene)piperidin-4″-ones and 1-methyl-4-arylpyrrolo-(spiro[2.11′]-11H-indeno[1,2-b]quinoxaline)-spiro[3.3″]-1″-methyl/benzyl-5″-(arylmethylidene)piperidin-4″-ones have been synthesized via 1,3-dipolar azomethine ylide cycloaddition in the ionic liquid, 1-butyl-3-methylimidazolium bromide ([BMIm]Br), in excellent yields. 相似文献
9.
Microwave irradiation allows increasing the speed of several reactions and also offers the possibility of eliminating poisoning organic solvents. In this work we report the microwave-assisted neat synthesis of α-phenyl-tert-butylnitrone (PBN) and other alkyl and aryl nitrones and also the rapid synthesis of isoxazolidines resulting from 1,3-dipolar cycloaddition of nitrones to ethyl trans-crotonate. 相似文献
10.
《Comptes Rendus Chimie》2016,19(8):933-935
The stereoselective 1,3-dipolar cycloaddition between (Z)-1,4-dichloro-2-butene and a menthone-derived nitrone led to the corresponding isoxazolidine. Regioselective azidation of a single chlorine atom followed by another Cu(I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition (CuAAC) induced enantiopure 1,2,3-triazolyl-functionalized isoxazolidines. The subsequent acidic cleavage of the menthone chiral auxiliary and reductive cleavage of the isoxazolidine N–O bond triggered an intramolecular cyclization through the displacement of the second chlorine. This rapid and stereoselective synthetic strategy provided reliable access to a series of enantiopure 3-substituted 4-hydroxyproline derivatives. 相似文献
11.
Combinatorial library of isoxazoles was prepared by 1,3-dipolar cycloaddition on solid support. p-Cyano derivatives showed nematic and/or smectic A phases. A bilayer smectic phase for 2h is proposed by the combination of molecular mechanics calculation and X-ray diffraction experiment. 相似文献
12.
Srivari Chandrasekhar Mallikanti SeenaiahAbhishek Kumar Chada Raji ReddySuman Kumar Mamidyala Chityal Ganesh KumarSridhar Balasubramanian 《Tetrahedron letters》2011,52(7):806-808
Synthesis of a series of [1,2,3] triazolo [5,1-c] [1,4]benzoxazepine derivatives have been accomplished by the intramolecular Cu(I)-catalyzed cycloaddition of azido-alkynes derived from salicylaldehyde. The biological profile of these heterocyclic structural scaffolds toward anti-bacterial as well as anti-fungal activity has also been illustrated. 相似文献
13.
Kwai Ming J. Cheung 《Tetrahedron letters》2010,51(45):5915-5918
We describe the synthesis of diverse pyrazoles by 1,3-dipolar cycloaddition of ethyl diazoacetate with various acetylenes in refluxing toluene. The product pyrazoles are useful starting points for preparing a diverse collection of trisubstituted pyrazole carboxamides. For aryl and heteroaryl alkynes a single product is obtained while alkyl alkynes afford a ca. 6:1 mixture of regioisomers. The observed regioselectivity for the cycloaddition step and the ease of reaction are consistent with predictions derived from computing the HOMO-LUMO energies of the reactants. 相似文献
14.
R. Rajesh 《Tetrahedron letters》2010,51(14):1896-1898
A facile and efficient one-pot synthesis of 12-15-membered triazolophanes has been accomplished using CuAAC methodology. The formation of triazolophanes was confirmed by spectral analysis and the products were isolated in good yield. The effect of solvents on this reaction was also studied. 相似文献
15.
《Tetrahedron letters》2019,60(35):150989
This communication details the first total synthesis of Punicagranine, a new pyrrolizine alkaloid isolated from the peels of the pomengranate, Punica granatum, the basis for traditional Chinese medicine, with anti-inflammatory activity. Two concise, 4–5 step routes were developed to rapidly prepare Punicagranine in 10.7–12.1% overall yields. One route features an intramolecular Heck reaction, while the other relies on a 1,3-dipolar cycloaddition. The latter route proceeds on scale to support future biological studies. 相似文献
16.
Antonino Lauria Annalisa Guarcello Gabriella Macaluso Anna Maria Almerico 《Tetrahedron letters》2009,50(52):7333-1004
The reactivity of asymmetric benzo-condensed diazines in the 1,3-dipolar cycloaddition reactions with nitrilimines was investigated. The results demonstrated that, at variance with the symmetric quinoxaline, a certain grade of diastereoselectivity emerged. Moreover in the case of the 5-methylquinoxaline and quinazoline a mono-cycloadduct was obtained. 相似文献
17.
A simple and convenient route for one-pot synthesis of cyclopenta[d]pyridazine through 1,3-dipolar cycloaddition of fulvenes and hydrazonyl chlorides is described. The reaction of fulvenes with hydrazonyl chlorides in the presence of silver carbonate smoothly afforded a series of cyclopenta[d]pyridazines. 相似文献
18.
《Comptes Rendus Chimie》2014,17(2):171-178
A variety of 4′-(4-R-phenyl)-4-(methylthio)-2′-phenyl-2′H-spiro[chromene-2,5′-[1,2,3]thiadiazole] 5a–d and 5′-(4-R-phenyl)-4-(methylthio)-3′-phenyl-3′H-spiro[chromene-2,2′-[1,3,4]thiadiazole] 6a–d were synthesized regioselectively through the reaction of 4-(methylthio)-2H-chromene-2-thione 2 with diarylnitrilimines under refluxing dry chloroform. Whilst the reaction of 4-(allylthio)-2H-chromene-2-thione 3 with diarylnitrilimines under similar reaction conditions afforded the corresponding 4-(allylthio)-5′-(4-R-phenyl)-3′-phenyl-3′H-spiro[chromene-2,2′-[1,3,4]thiadiazole] 7a–d and 5-(4-R-phenyl)-2′-methyl-3-phenyl-2′,3′-dihydro-3H-spiro[[1,3,4]thiadiazole-2,4′-thieno[3,2-c]chromene] 9a–d as two unisolable diastereoisomeric forms. The structures of the obtained spiro cycloadduct thiadiazoles have been assigned by means of spectroscopic measurements. 相似文献
19.
Srinivas Chittaboina 《Tetrahedron letters》2005,46(13):2331-2336
Highly efficient one-pot synthesis of 1,2,3-triazole-linked glycoconjugates was presented involving a Cu(I) catalyzed 1,3-dipolar cycloaddition as the key step. It offers a convenient route to prepare neoglycoconjugates derived from unprotected saccharides or peracetylated saccharides. 相似文献
20.
Mark J. Thompson 《Tetrahedron letters》2006,47(14):2361-2364
A convenient route to 4-phenyl-5-aminothiazoles is described, which offers control over substitution at the 2-position. 2-N-Acylglycinamides were dithionated and a subsequent TFAA-mediated cyclisation step was followed by removal of the 5-N-trifluoroacetyl group providing the free amines. Though applicable generally the method was found to be most effective when introducing aromatic substituents at the 2-position, whereupon moderate overall yields of the 5-amino compounds were obtained. 相似文献