Copper(I)-Catalyzed Azide-Alkyne Cycloadditions in Ionic Liquids under Amine-Free Conditions

Abstract

Copper(I) iodide catalyzed cycloadditions of various combinations of structurally diverse organic azides and terminal alkynes were carried out in a commercially available, polyoxygenated ionic liquid (AMMOENG 100™) without addition of free amine. Unlike the previously tested ionic liquids, this solvent led exclusively to the 1,4-disubstituted triazole regioisomer.

Key words

alkynes - azides - carbohydrates - copper - cycloadditions

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14

The model reaction between 2 and 7, carried out at 80 ˚C by heating with an oil bath, was also complete after 2 h and afforded exclusively the 1,4-disubstituted triazole derivative 14 in the same isolated yield (68%).