Synthesis of 1,2,3-Triazoles from Alkyne-Azide Cycloaddition Catalyzed by a Bio-Reduced Alkynylcopper (I) Complex

Abstract

A small library of 1,2,3-triazoles was synthesized from diverse alkynes and azides using catalytic amounts of an alkynylcopper (I) complex, which in turn was prepared from direct treatment of phenylacetylene with a Fehling reagent in the presence of glucose as a reducing agent. The results suggest that copper-catalyzed azide alkyne cycloaddition (CuAAC) reactions require only 0.5 mg/mmol copper (I) phenylacetylide without any further additives.

Versatile Synthetic Platform for 1,2,3-Triazole Chemistry

“…Varela-Palma and co-workers 79 developed a synthesis of 1-(1-benzyl-1,2,3-triazol-4-yl)cyclohexanol 124 from 1-ethynylcyclohexanol 123 and benzyl azide 76 using phenylethynylcopper(I) 122 catalyst and CH 2 Cl 2 as a solvent at RT for 24 h. Adding a Fehling A and B solution to the glucose–phenylacetylene 46 mixture resulted in yellow particles such as phenylethynylcopper(I). The 1,3-bis(1,2,3-triazol-1-yl)-propan-2-ol core containing a triazole (10 examples) was synthesized by this protocol with 80–92% yields ( Scheme 27 ).…”