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Aly AA, Hassan AA, Mohamed NK, Ramadan M, Brown AB, Abd El-Aal AS, Bräse S, Nieger M. Regioselective formation of 1,2,4-triazoles by the reaction of amidrazones in the presence of diethyl azodicarboxylate and catalyzed by triethylamine. Mol Divers 2018; 23:195-203. [PMID: 30105556 DOI: 10.1007/s11030-018-9868-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Accepted: 08/02/2018] [Indexed: 11/25/2022]
Abstract
A general method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazoles has been developed from reaction of amidrazones with ethyl azodicarboxylate and triethylamine (Mitsunobu reagent) in EtOH. This highly regioselective one-pot process provides rapid access to highly diverse triazoles. The reaction was explained, based on Mitsunobu reagent oxidizing ethanol to acetaldehyde, which would then react with amidrazones to give the substituted 3-methyltriazoles. A [2 + 3] cycloaddition reaction between two oxidized forms of amidrazones produced the second type of triazoles. X-ray structure analyses proved the structure of each type of product.
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Affiliation(s)
- Ashraf A Aly
- Chemistry Department, Faculty of Science, Minia University, El-Minia, 61519, Egypt.
| | - Alaa A Hassan
- Chemistry Department, Faculty of Science, Minia University, El-Minia, 61519, Egypt
| | - Nasr K Mohamed
- Chemistry Department, Faculty of Science, Minia University, El-Minia, 61519, Egypt
| | - Mohamed Ramadan
- Organic Pharmacy Department, Faculty of Pharmacy, Al-Azhar Branch of Assiut University, Assiut, Egypt
| | - Alan B Brown
- Chemistry Department, Florida Institute of Technology, Melbourne, FL, 32901, USA
| | - Amal S Abd El-Aal
- Chemistry Department, Faculty of Science, Minia University, El-Minia, 61519, Egypt
| | - Stefan Bräse
- Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany
| | - Martin Nieger
- Department of Chemistry, University of Helsinki, PO Box 55, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
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