- 5-Aryltetrazoles from Direct C-H Arylation with Aryl Bromides
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A mild, direct C-H arylation of 1-substituted tetrazoles to 5-aryltetrazoles is developed using a Pd/Cu cocatalytic system with readily available aryl bromides. The methodology avoids late-stage usage of azides and tolerates a wide range of functionalities.
- Zhang, Yuan,Lee, Jack Chang Hung,Reese, Matthew R.,Boscoe, Brian P.,Humphrey, John M.,Helal, Christopher J.
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p. 5718 - 5723
(2020/05/19)
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- Photophysical and biological investigation of phenol substituted rhenium tetrazolato complexes
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The synthesis, structural and photophysical characterisation of four tricarbonyl rhenium(i) complexes bound to 1,10-phenanthroline and a tetrazolato ancillary ligand are reported. The complexes are differentiated by the nature (hydroxy or methoxy) and pos
- Akabar, Nurshadrina,Chaturvedi, Vishal,Shillito, Georgina E.,Schwehr, Bradley J.,Gordon, Keith C.,Huff, Gregory S.,Sutton, Joshua J.,Skelton, Brian W.,Sobolev, Alexandre N.,Stagni, Stefano,Nelson, Delia J.,Massi, Massimiliano
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p. 15613 - 15624
(2019/11/05)
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- Enhanced Thermocatalytic Activity of Porous Yellow ZnO Nanoflakes: Defect- and Morphology-Induced Perspectives
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Herein, we report a simple and effective strategy for the synthesis of yellow ZnO (Y-ZnO) nanostructures with abundant oxygen vacancies on a large scale, through the sulfidation of ZnO followed by calcination. The developed strategy allows retention of the overall morphology of Y-ZnO compared with pristine ZnO and the extent of oxygen vacancies can be tuned. The influence of oxygen deficiencies, the extent of defect sites, and the morphology of ZnO on its solution-phase thermocatalytic activity has been evaluated in the synthesis of 5-substituted-1H-tetrazoles with different nitriles and sodium azide. A reasonable enhancement in the reaction rate was achieved by using Y-ZnO nanoflakes (Y-ZnO NFs) as a catalyst in place of pristine ZnO NFs. The reaction was complete within 6 h at 110 °C with Y-ZnO NFs, whereas it took 14 h at 120 °C with pristine ZnO NFs. The catalyst is easy to recycle without a significant loss in catalytic activity.
- Galani, Sunil M.,Panda, Asit Baran
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p. 612 - 620
(2019/02/14)
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- Tin-Catalyzed Synthesis of 5-Substituted 1H-Tetrazoles from Nitriles: Homogeneous and Heterogeneous Procedures
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The preparation of 5-substituted 1H-tetrazoles was efficiently achieved by reaction of trimethylsilylazide with nitriles using a triorganotin alkoxide precatalyst. The reaction mechanism was first investigated using a homogeneous tributyltin derivative and was explored through experimental investigations and DFT calculations. A heterogeneous version was then developed using a polymer-supported organotin alkoxide and afforded an efficient method for the preparation of tetrazoles in high yields with an easy work-up and a residual tin concentration in the desired products compatible for pharmaceutical applications (less than 10 ppm). (Figure presented.).
- Chrétien, Jean-Mathieu,Kerric, Gaelle,Zammattio, Fran?oise,Galland, Nicolas,Paris, Michael,Quintard, Jean-Paul,Le Grognec, Erwan
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supporting information
p. 747 - 757
(2019/01/04)
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- Discovery, synthesis and characterization of a series of (1-alkyl-3-methyl-1H-pyrazol-5-yl)-2-(5-aryl-2H-tetrazol-2-yl)acetamides as novel GIRK1/2 potassium channel activators
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The present study describes the discovery and characterization of a series of 5-aryl-2H-tetrazol-3-ylacetamides as G protein-gated inwardly-rectifying potassium (GIRK) channels activators. Working from an initial hit discovered during a high-throughput screening campaign, we identified a tetrazole scaffold that shifts away from the previously reported urea-based scaffolds while remaining effective GIRK1/2 channel activators. In addition, we evaluated the compounds in Tier 1 DMPK assays and have identified a (3-methyl-1H-pyrazol-1-yl)tetrahydrothiophene-1,1-dioxide head group that imparts interesting and unexpected microsomal stability compared to previously-reported pyrazole head groups.
- Sharma, Swagat,Kozek, Krystian A.,Abney, Kristopher K.,Kumar, Sushil,Gautam, Nagsen,Alnouti, Yazen,David Weaver,Hopkins, Corey R.
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p. 791 - 796
(2019/02/06)
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- Cationic organotin cluster [t-Bu2Sn(OH)(H2O)]2 2+2OTf?-catalyzed one-pot three-component syntheses of 5-substituted 1H-tetrazoles and 2,4,6-triarylpyridines in water
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The cationic organotin cluster [t-Bu2Sn(OH)(H2O)]2 2+2OTf? is easy to prepare and stable in air. The catalytic activity of [t-Bu2Sn(OH)(H2O)]2 2+2OTf? as a neutral organotin Lewis acid catalyst is probed through the one-pot three-component syntheses of 5-substituted 1H-tetrazoles from aldehydes, hydroxylamine hydrochloride and sodium azide, and of 2,4,6-triarylpyridines from aromatic aldehydes, substituted acetophenones and ammonium acetate. The reactions proceed well in the presence of 1?mol% of [t-Bu2Sn(OH)(H2O)]2 2+2OTf? in water and provide the corresponding 5-substituted 1H-tetrazoles and 2,4,6-triarylpyridines in good to excellent yields. The method reported has several advantages such as the catalyst being neutral, low catalyst loading and use of water as a green solvent.
- Wang, Hongshe,Zhao, Weixing,Du, Juan,Wei, Fenyan,Chen, Qi,Wang, Xiaomei
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- Humic acid as an efficient and reusable catalyst for one pot three-component green synthesis of 5-substituted 1: H -tetrazoles in water
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Humic acid is a non toxic, inexpensive, easily available high-molecular weight polymer. A simple and facile one pot three-component synthesis of 5-substituted 1H-tetrazoles from aldehydes, hydroxyamine hydrochloride and sodium azide using humic acid as an efficient catalyst in water is described. The method reported has several advantages such as high to excellent yields, easy work-up, mild reaction conditions, use of water as a green solvent, and a commercially available, nontoxic and reusable catalyst.
- Wang, Hongshe,Wang, Yichun,Han, Yinfeng,Zhao, Weixing,Wang, Xiaomei
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p. 784 - 789
(2020/01/23)
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- Tandem magnetization and post-synthetic metal ion exchange of metal–organic framework: Synthesis, characterization and catalytic study
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For the first time, metal-exchange in a magnetic metal–organic framework (MOF) via tandem magnetization and post-synthetic modification has been developed. The new magnetic mixed-metal metal–organic framework nanocomposite, CoFe2O4/[
- Yadollahi, Mahtab,Hamadi, Hosein,Nobakht, Valiollah
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- Engineering a Cu-MOF Nano-Catalyst by using Post-Synthetic Modification for the Preparation of 5-Substituted 1H-Tetrazoles
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A new nano scale Cu-MOF has been obtained via post-synthetic metalation by immersing a Zn-MOF as a template in DMF solutions of copper(II) salts. The Cu-MOF serves as recyclable nano-catalyst for the preparation of 5-substituted 1H-tetrazoles via [3?+?2] cycloaddition reaction of various nitriles and sodium azide in a green medium (PEG). The post-synthetic metalated MOF were characterized by FT-IR spectroscopy, powder X-ray diffraction (PXRD), atomic absorption spectroscopy (AAS), and energy dispersive X-ray spectroscopy (EDX) techniques. The morphology and size of the nano-catalyst were determined by field emission scanning electron microscopy (FE-SEM).
- Salahshournia, Behrang,Hamadi, Hosein,Nobakht, Valiollah
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- Synthesis of tetrazoles, triazoles, and imidazolines catalyzed by magnetic silica spheres grafted acid
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The magnetically separable catalysts are used in the synthesis of N-containing heterocycles, including tetrazoles, triazoles, and imidazolines. The magnetic silica sphere grafted sulfonic acid (MSS-SO3H) is suitable for the synthesis of 1,2,3-triazole via the cycloaddition of nitroalkene with NaN3, whereas the zinc-modified silica sphere catalyst (MSS-SO3Zn) is more suitable for the synthesis of tetrazoles. The MSS-SO3Zn catalyst also works well for the synthesis of 2-substituted imidazoline via the condensation of nitriles with ethylenediamine. Both of the MSS-SO3H and MSS-SO3Zn catalysts can be recovered easily by a magnet, and they can be reused without further tedious activation.
- Jiang, Ruihang,Sun, Hong-Bin,Li, Shuang,Zhan, Kun,Zhou, Junjie,Liu, Lei,Zhang, Kai,Liang, Qionglin,Chen, Zhangpei
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supporting information
p. 2652 - 2662
(2018/11/26)
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- Efficient synthesis of 5-substituted 1H-tetrazoles catalysed by silver(I) bis(trifluoromethanesulfoyl)nimide
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An efficient method is developed for the synthesis of 5-substituted 1H-tetrazoles through the [3 + 2] cycloaddition reaction of nitriles with sodium azide using silver(I) bis(trifluoromethanesulfonyl)imide (AgNTf2) as a catalyst. This procedure provides mild reaction conditions, short reaction times and high yields.
- Wang, Hongshe,Zhao, Weixing
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p. 321 - 323
(2015/08/11)
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- Organocatalysis by an aprotic imidazolium zwitterion: A dramatic anion-cation cooperative effect on azide-nitrile cycloaddition
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An aprotic imidazole based zwitterionic-salt, 4-(3-methylimidazolium)butane sulfonate (MBS) has been found to be an efficient organocatalyst for the synthesis of 5-substituted 1H-tetrazoles by the cycloaddition of aryl nitriles with NaN3 under solvent-free conditions. Both the cation and the anion cooperatively affect the reaction and the C2-H of the imidazolium moiety plays a crucial role in "electrophilic activation" of the nitrile through hydrogen bond formation.
- Rahman, Matiur,Roy, Anupam,Ghosh, Monoranjan,Mitra, Shubhanjan,Majee, Adinath,Hajra, Alakananda
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p. 6116 - 6119
(2014/01/23)
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- CuFe2O4 nanoparticle mediated method for the synthesis of 5-substituted 1H-tetrazoles from (E)-aldoximes
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A strategy for the synthesis of 5-substituted 1H-tetrazoles from various (E)-aldoximes and sodium azide was adopted using copper ferrite nanoparticles as a reusable catalyst.
- Akula, Ravi Kumar,Adimulam, Chandra S.,Gangaram, Sathaiah,Kengiri, Raju,Banda, Narsaiah,Pamulaparthy, Shanthan R.
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p. 440 - 445
(2014/05/20)
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- Ligand-free nano copper oxide catalyzed cyanation of aryl halides and sequential one-pot synthesis of 5-substituted-1H-tetrazoles
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An expedient and sequential one-pot synthesis of 5-substituted-1H- tetrazoles via [2+3] cycloaddition of aryl nitriles with sodium azide is reported. The required aryl nitriles were synthesized via the nano-copper oxide promoted cyanation of aryl iodides generated in situ.
- Yapuri, Umanadh,Palle, Sadanandam,Gudaparthi, Omprakash,Narahari, Srinivasa Reddy,Rawat, Dhwajbahadur K.,Mukkanti, Khagga,Vantikommu, Jyothi
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p. 4732 - 4734
(2013/08/23)
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- Heteropolyacid catalyzed click synthesis of 5-substituted 1H-tetrazoles from [bmim]N3 and nitriles under solvent-free conditions
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A simple and solvent-free route for the synthesis of 5-substituted 1H-tetrazoles is reported. In this method, 5-substituted 1H-tetrazoles are synthesized from nitriles and [bmim]N3 with heteropolyacid (H 3PW12O40/sub
- Fazeli, Azadeh,Oskooie, Hossein A.,Beheshtiha, Yahya S.,Heravi, Majid M.,Valizadeh, Hassan,Bamoharram, Fatemeh F.
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p. 1407 - 1410
(2013/10/01)
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- An experimental and computational assessment of acid-catalyzed azide-nitrile cycloadditions
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The mechanism of the azidea-nitrile cycloaddition mediated by different Bronsted and Lewis acids has been addressed through DFT calculations. In all cases activation of the nitrile substrate by the Bronsted or Lewis acid catalyst was found to be responsib
- Cantillo, David,Gutmann, Bernhard,Kappe, C. Oliver
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p. 10882 - 10890
(2013/02/22)
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- CuFe2O4 nanoparticles: A magnetically recoverable and reusable catalyst for the synthesis of 5-substituted 1H-tetrazoles
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An efficient and economical protocol for the synthesis of 5-substituted 1H-tetrazoles from various nitriles and sodium azide is described using magnetically recoverable and reusable CuFe2O4 nanoparticles. A wide variety of aryl nitriles underwent [2+3] cycloaddition under mild reaction conditions to afford tetrazoles in good to excellent yields. The catalyst was magnetically separated and reused five times without significant loss of catalytic activity.
- Sreedhar,Kumar, A. Suresh,Yada, Divya
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experimental part
p. 3565 - 3569
(2011/07/29)
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- A versatile and an efficient synthesis of 5-substituted-1H-tetrazoles
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A simple, efficient and a versatile method for the synthesis of 5-substituted-1H-tetrazoles by a [3+2]-cycloaddition reaction of arylnitriles with sodium azide in DMF using ZrOCl2.8 H2O as catalyst has been developed. The reactions work well at 100°C and give the desired products in excellent yield. The examples studied include arylnitriles having electron donating as well as electron releasing groups on the arene nucleus. Indian Academy of Sciences.
- Gowd, Madhusudana Reddy Muthukur Bhoje,Pasha, Mohamed Afzal
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experimental part
p. 75 - 79
(2012/01/13)
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- Mechanistic insights on azide-nitrile cycloadditions: On the dialkyltin oxide-trimethylsilyl azide route and a new vilsmeier-haack-type organocatalyst
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The mechanism of the azide-nitrile cycloaddition mediated by the known dialkylltin oxide-trimethylsilyl azide catalyst system has been addressed through DFT calculations. The catalytic cycle for this tin/silicon complex-based mechanism has been thoroughly examined, disclosing the most plausible intermediates and the energetics involved in the rate enhancement. In addition, a new catalyst, 5-azido-1-methyl-3,4-dihydro-2H-pyrrolium azide, is presented for the formation of tetrazoles by cycloaddition of sodium azide with organic nitriles under neutral conditions. The efficiency of this organocatalyst, generated in situ from N-methyl-2-pyrrolidone (NMP), sodium azide, and trimethylsilyl chloride under reaction conditions, has been examined by preparation of a series of 5-substituted-1H-tetrazoles. The desired target structures were obtained in high yields within 15-25 min employing controlled microwave heating. An in depth computational analysis of the proposed catalytic cycle has also been addressed to understand the nature of the rate acceleration. The computed energy barriers have been compared to the dialkylltin oxide-trimethylsilyl azide metal-based catalyst system. Both the tin/silicon species and the new organocatalyst accelerate the azide-nitrile coupling by activating the nitrile substrate. As compared to the dialkylltin oxide-trimethylsilyl azide method, the organocatalytic system presented herein has the advantage of higher reactivity, in situ generation from inexpensive materials, and low toxicity.
- Cantillo, David,Gutmann, Bernhard,Kappe, C. Oliver
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experimental part
p. 4465 - 4475
(2011/05/14)
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- Aluminum(III) hydrogensulfate: An efficient solid acid catalyst for the preparation of 5-substituted 1H-tetrazoles
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An efficient method for preparation of 5-substituted 1H-tetrazoles via [2+3] cycloaddition of nitriles and sodium azide is reported using aluminum(III) hydrogensulfate as an effective solid acid. This method has the advantages of good yields, simple methodology, and easy workup. Copyright
- Sajadi, S. Mohammad,Khalaj, Mehdi,Jamkarani, Sayyed Mohammad Hosseini,Maham, Mehdi,Kashefib, Mehrdad
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scheme or table
p. 3053 - 3059
(2011/09/12)
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- Montmorillonite K-10 clay as an efficient reusable heterogeneous catalyst for the solvent-free microwave mediated synthesis of 5-substituted 1H-tetrazoles
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Various 5-substituted 1H-tetrazole derivatives were synthesized in a simple and environmentally benign method from the reaction of aryl and benzyl nitriles with sodium azide in solvent-free media using montmorillonite K-10 clay as solid recyclable heterogeneous acidic catalyst and microwave irradiation in good yields and short reaction times. Copyright
- Marvi, Omid,Alizadeh, Abdolhamid,Zarrabi, Saeid
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experimental part
p. 4001 - 4004
(2012/04/10)
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- Iodine-catalyzed, efficient, one-pot protocol for the conversion of araldehydes into 5-aryl-1H-tetrazoles
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An easy access to various 5-aryl-1H-tetrazoles by a one-pot direct conversion of aldehydes to tetrazoles without the isolation of the intermediate nitriles using commercially available iodine as a catalyst is described. The protocol offers advantages in terms of good yields, mild reaction conditions, short reaction times, and use of readily available environmentally compatible catalyst. Copyright
- Reddy, M.B.Madhusudana,Pasha
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experimental part
p. 2081 - 2085
(2011/07/07)
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- Synthesis of 5-substituted lH-tetrazoles from nitriles and hydrazoic acid by using a safe and scalable high-temperature microreactor approach
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Harnessing hydrazoic acid in a microreactor! Tetrazoles have been synthesized in a very efficient manner by using a high-temperature/high-pressure process intensification regime. Despite the toxic and explosive nature of hydrazoic acid, the synthesis was conducted safely in continuous flow format with residence times as short as 2.5 minutes at 260□°C (see picture).
- Gutmann, Bernhard,Roduit, Jean-Paul,Kappe, C. Oliver,Roberge, Dominique
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supporting information; experimental part
p. 7101 - 7105
(2010/11/05)
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- FeCl3-SiO2 as a reusable heterogeneous catalyst for the synthesis of 5-substituted 1H-tetrazoles via [2+3] cycloaddition of nitriles and sodium azide
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An efficient method for the preparation of 5-substituted 1H-tetrazole derivatives is reported using FeCl3-SiO2 as an effective heterogeneous catalyst. This method has the advantages of high yields, simple methodology, and easy work-up. The catalyst can be recovered by simple filtration and reused delivering good yields.
- Nasrollahzadeh, Mahmoud,Bayat, Yadollah,Habibi, Davood,Moshaee, Saeed
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experimental part
p. 4435 - 4438
(2009/11/30)
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- TBAF-Catalyzed Synthesis of 5-Substituted 1H-Tetrazoles under Solventless Conditions
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Tetrabutylammonium fluoride (TBAF) is an efficient catalyst in the [3 + 2] cycloaddition reaction of organic nitriles 1 with trimethylsilyl azide (TMSN3) in solventless conditions. The corresponding 5-substituted 1H-tetrazoles 2 were obtained under mild conditions and in 80-97% yields.
- Amantini, David,Beleggia, Romina,Fringuelli, Francesco,Pizzo, Ferdinando,Vaccaro, Luigi
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p. 2896 - 2898
(2007/10/03)
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