Synthesis 2013; 45(17): 2372-2386
DOI: 10.1055/s-0033-1339312
feature article
© Georg Thieme Verlag Stuttgart · New York

Synthesis of 5-Iodo-1,2,3-triazoles from Organic Azides and Terminal Alkynes­: Ligand Acceleration Effect, Substrate Scope, and Mechanistic Insights

David N. Barsoum
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
Christopher J. Brassard
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
Jason H. A. Deeb
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
Najeah Okashah
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
Kesavapillai Sreenath
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
J. Tyler Simmons
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
,
Lei Zhu*
Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306-4390, USA   Fax: +1(850)6448281   Email: [email protected]
› Author Affiliations
Further Information

Publication History

Received: 26 March 2013

Accepted after revision: 06 June 2013

Publication Date:
19 July 2013 (online)


Abstract

An improved method has been developed for the preparation of 5-iodo-1,2,3-triazoles directly from organic azides and terminal alkynes by a reaction mediated by copper(I) and iodinating agents generated in situ. The major methodological advance of the current procedure is that it provides a high conversion and good iodo/proto selectivity with a broad range of substrates without using an excess of the alkyne, which was required in the previous method. The use of an accelerating ligand is essential to the success of reactions involving unreactive azides or alkynes. New mechanistic insights are provided, including the confirmation that a 1-iodoalkyne is formed as a key intermediate under the established conditions for the reaction.

Supporting Information

 
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