- A novel one-pot method for the preparation of pyrazoles by 1,3-dipolar cycloadditions of diazo compounds generated in situ.
A novel one-pot method for the preparation of pyrazoles by 1,3-dipolar cycloadditions of diazo compounds generated in situ.
The Journal of organic chemistry (2003-06-21)
Varinder K Aggarwal, Javier de Vicente, Roger V Bonnert
PMID12816503
ABSTRACT
A convenient one-pot procedure for the preparation of pyrazoles by 1,3-dipolar cycloaddition of diazo compounds generated in situ has been developed. Diazo compounds derived from aldehydes were reacted with terminal alkynes to furnish regioselectively 3,5-disubstituted pyrazoles. Furthermore, the reaction of N-vinylimidazole and diazo compounds derived from aldehydes gave exclusively 3-substituted pyrazoles in a one-pot process.
MATERIALS