Alkynes and Nitrogen Compounds: Useful Substrates for the Synthesis of Pyrazoles
1Department of Biochemistry and Molecular Biology Laboratório de Síntese, Reatividade, Avaliação Farmacológica e Toxicológica de Organocalcogênios, CCNE, Universidade Federal de Santa Maria, Santa Maria, Rio Grande do Sul, 97105-900, Brazil.
Abstract:
The easy preparation and functionalization of pyrazoles associated with their innumerable biological properties have made this class of N-heterocycles very attractive for the development of new synthetic routes and applications. The cyclization reactions of alkynes and nitrogen compounds represent a powerful tool for the preparation of pyrazoles. This Review covers the recent advances in the preparation of pyrazoles by reacting alkynes and nitrogen compounds under transition-metal-catalyzed or metal-free conditions.
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