Force-induced retro-click reaction of triazoles competes with adjacent single-bond rupture

• Verfasst von: Stauch, Tim [VerfasserIn]
• Verfasst von: Dreuw, Andreas [VerfasserIn]
• Titel: Force-induced retro-click reaction of triazoles competes with adjacent single-bond rupture
• Verf.angabe: Tim Stauch and Andreas Dreuw
• Umfang: 9 S.
• Fussnoten: Gesehen am 14.09.2018
• Titel Quelle: Enthalten in: Chemical science
• Jahr Quelle: 2017
• Band/Heft Quelle: 8(2017), 8, S. 5567-5575
• ISSN Quelle: 2041-6539
• DOI: doi:10.1039/C7SC01562C
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1580976425

Abstract

The highly controversial force-induced cycloreversion of 1,2,3-triazole, its well-known retro-click reaction, is shown to be possible only for 1,5-substituted triazoles, but competes with rupture of an adjacent single-bond. We draw this conclusion from both static and dynamic calculations under external mechanical forces applied to unsubstituted and 1,4- and 1,5-substituted triazoles. The JEDI (Judgement of Energy DIstribution) analysis, a quantum chemical tool quantifying the distribution of strain energy in mechanically deformed molecules, is employed to identify the key factors facilitating the force-induced retro-click reaction in these systems. For 1,4-substituted triazoles it is shown to be impossible, but the parallel alignment of the scissile bond in 1,5-substituted triazoles with the acting force makes it generally feasible. However, the weakness of the carbon-nitrogen bond connecting the triazole ring to the linker prevents selective cycloreversion.