An Organocatalytic Regiospecific Synthesis of 1,5-Disubstituted 4-Thio-1,2,3-triazoles and 1,5-Disubstituted
Dhevalapally B Ramachary1, Patoju M Krishna2, Jagjeet Gujral2
1Catalysis Laboratory, School of Chemistry, University of Hyderabad, Hyderabad-500 046 (India), Fax: (+91)40-23012460 http://chemistry.uohyd.ernet.in/∼dbr/. ramsc@uohyd.ernet.in, ramchary.db@gmail.com.
Abstract:
Organocatalytic azide-ketone [3+2] cycloaddition (OrgAKC) of a variety of 1-aryl-2-(arylthio)ethanones and 1-alkyl-2-(alkylthio)ethanones with different aryl or alkyl azides is reported in dimethyl sulfoxide or solvent-free under ambient conditions to furnish 1,5-disubstituted 4-thio-1,2,3-triazoles in a regiospecific manner, which are further converted into useful 1,5-disubstituted 1,2,3-triazoles by treatment with Raney Ni at 25 °C for 1-3 h. Notable features of the OrgAKC reaction include high rate and selectivity, solvent-free conditions, easily available substrates and catalysts, a wide range of synthetic and medicinal applications, and excellent yields generating a vast library of triazoles.
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