1472652-05-3Relevant academic research and scientific papers
Facile Access to Triazole-Fused 3,1-Benzoxazines Enabled by Metal-Free Base-Promoted Intramolecular C-O Coupling
Tatevosyan, Stepan S.,Kotovshchikov, Yury N.,Latyshev, Gennadij V.,Lukashev, Nikolay V.,Beletskaya, Irina P.
, p. 369 - 377 (2021/10/21)
A convenient approach to assemble 1,2,3-triazole-fused 4 H -3,1-benzoxazines has been developed. Diverse alcohol-tethered 5-iodotriazoles, readily accessible by a modified protocol of Cu-catalyzed (3+2)-cycloaddition, were utilized as precursors of the target fused heterocycles. The intramolecular C-O coupling proceeded efficiently under base-mediated transition-metal-free conditions, furnishing cyclization products in yields up to 96%. Suppression of the competing reductive cleavage of the C-I bond was achieved by the use of Na 2CO 3in acetonitrile at 100 °C. This practical and cost-effective procedure features a broad substrate scope and valuable functional group tolerance.
Synthesis of 5-Iodo-1,2,3-triazoles from organic azides and terminal alkynes: Ligand acceleration effect, substrate scope, and mechanistic insights
Barsoum, David N.,Brassard, Christopher J.,Deeb, Jason H. A.,Okashah, Najeah,Sreenath, Kesavapillai,Simmons, J.Tyler,Zhu, Lei
, p. 2372 - 2386 (2013/09/23)
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.
