Copper(I)‐Catalyzed Cycloaddition of Organic Azides and 1‐Iodoalkynes

Abstract

High fidelity: 1‐Iodoalkynes react rapidly and selectively with organic azides in the presence of copper(I) catalysts (see scheme; TTTA=tris((1‐tert‐butyl‐1H‐1,2,3‐triazolyl)methyl)amine). The reaction is compatible with many functional groups and solvents, and 5‐iodotriazole products were usually obtained in excellent yield. These products can be further functionalized to give fully substituted 1,2,3‐triazoles.

Synthesis by Click Reactions and Antiplasmodial Activity of Lupeol 1,2,3-Triazole Derivatives

“…22 Its IR spectrum showed characteristic bands in These signals confirm the insertion of a propargyl group in the lupeol structure. 22 The spectrum of 13 displayed common signals with lupeol, 28,29 The CuAAC, often referred to as "click reaction", occurred between the terminal alkyne of the lupeol propargyl ether (13) and known organic azides [17][18][19]21 that were previously synthesized. 22 CuAAc is known for its high efficiency without need for special reaction conditions, such as high temperature and/or high pressure, and is regioselective giving only the 1,4-disubstituted isomer.…”

“…22 CuAAc is known for its high efficiency without need for special reaction conditions, such as high temperature and/or high pressure, and is regioselective giving only the 1,4-disubstituted isomer. [17][18][19] The conditions of the click reactions used to prepare 14a-e (24 hours of reaction, dichloromethane and water as solvents) were similar to those previously described. 21,22 The products were obtained with yields ranging from 45 to 75%.…”

“…16 The CuAAC has been explored because of interesting characteristics such as mild reaction conditions, easy to execute, regioespecificity (only the 1,4-disubstituted isomer is obtained) and good yields. [17][18][19] In this paper we report the isolation of lupeol from Parahancornia fasciculata, synthesis of five 1,2,3-triazole derivatives of this triterpene by click chemistry, their evaluation for in vitro activity against chloroquine resistant P. falciparum W2 strain and cytotoxicity against Hep G2 cells.…”

A reação "click" na síntese de 1,2,3-triazóis: aspectos químicos e aplicações

“…12 Além disso, sob certas condições, 5-iodotriazóis já foram isolados. 28 Altas concentrações de íons cloreto em água também já se mostraram prejudiciais à reação. Dessa forma, o uso de brometo ou acetato cuproso é o mais indicado para reações em meio aquoso, onde se empregam diretamente íons Cu(I) como fonte de cobre.…”

Well-defined copper(i) complexes for Click azide–alkyne cycloaddition reactions: one Click beyond

“…A combination of TTTA 15 and CuI (5 mol %) provided good to excellent yields at room temperature after short reaction times (Scheme 14). 94 Pre-formed catalyst 45 led to similarly notable results with lower copper loading of 2 mol % in aqueous media. 95 Remarkably, in both cases, filtration or extraction techniques yielded directly analytically pure products.…”