Synthesis of 4,5-Diaryl-2H-1,2,3-triazoles from Tosylhydrazones and Nitriles
Potassium tert-Butoxide Promoted Synthesis of 4,5-Diaryl-2H-1,2,3-triazoles from Tosylhydrazones and Nitriles: S. Qiu, Y. Chen, X. Song, L. Liu, X. Liu, L. Wu
4,5-Diaryl-2H-1,2,3-triazoles are important molecules in medicinal chemistry and drug discovery, often showing a broad range of bioactivities spanning from cancer cell growth to protease inhibition. The synthesis of these compounds generally relies on the [3+2] cycloaddition between diaryl alkynes and trimethylsilyl or sodium azide, but the explosive instability and toxicity of the latter constitutes a significant problem, especially on larger reaction scales. Recently, the group of Dr. Luyong Wu from Hainan Normal University (P. R. of China) reported a new entry to the title compounds, which holds promise to address the existing experimental issues.
Dr. Wu said: “4,5-Diaryl NH-1,2,3-triazoles are obtained from N-tosylhydrazones with nitriles in high yields and high purities, and potassium tert-butoxide in xylene is the critical factor to restrain the homocoupling of N-tosylhydrazones.”