Construction of pyrazolone analogues via rhodium-catalyzed C–H activation from pyrazolones and non-activated free allyl alcohols

Abstract

Highly efficient rhodium(III) catalysis was developed for obtaining structurally divergent pyrazolone analogues from pyrazolones and non-activated free allyl alcohols. Notably, this new C–H activation reaction generated unexpected pyrazolo[1,2-α]cinnoline derivatives besides γ-ketone substituted edaravone derivatives, and the selectivity of this coupling reaction could be controlled by changing the conditions.