An easy-to-prepare, reusable and versatile catalyst consisting of oxidised copper nanoparticles on activated carbon has been fully characterised and found to effectively promote the multicomponent synthesis of 1,2,3-triazoles from organic halides, diazonium salts, and aromatic amines in water at a low copper loading.
An Organocatalytic Azide-Aldehyde [3+2] Cycloaddition: High-Yielding Regioselective Synthesis of 1,4-Disubstituted 1,2,3-Triazoles
作者:Dhevalapally B. Ramachary、Adluri B. Shashank、S. Karthik
DOI:10.1002/anie.201406721
日期:2014.9.22
An organocatalyticazide–aldehyde [3+2] cycloaddition (organo‐click) reaction of a variety of enolizable aldehydes is reported. The organo‐click reaction is characterized by a high rate and regioselectivity, mild reaction conditions, easily available substrates with simple operation, and excellent yields with a broad spectrum of substrates. It constitutes an alternative to the previously known CuAAC
NNNifty targets: In a straightforward copper‐mediated synthesis of 1,4‐disubstituted and 1,4,5‐trisubstituted 1,2,3‐triazoles, readily available aniline and N‐tosylhydrazone substrates underwent cyclization through CN and NN bond formation (see scheme; Piv=pivaloyl, Ts=p‐toluenesulfonyl). This method enables the preparation of 1,2,3‐triazoles with high efficiency under mild conditions without the
A novel synthetic approach toward 1,4‐disubstituted 1,2,3‐triazoles by CN‐ and NN‐bond formation has been established under transition‐metal‐free conditions. Complete control of the regioselectivity was successfully achieved. Commercially available anilines, ketones, and N‐tosylhydrazine were treated with molecular iodine in one pot to allow the regioselective generation of 1,4‐disubstituted 1,2