Abstract An efficient Rh-(III)-catalyzed C-H functionalization of N-ethoxybenzamides with 1-alkynylcyclobutanols has been developed. Isoquinolone derivatives have been successfully synthesized through [4 + 2] annulation and ring opening reaction under mild conditions. The advantages of this efficient protocol include broad substrate scope and good to excellent yields. Graphical Abstract
A Rhodium(III)-catalyzed [4+1] annulation and ring opening of 1 alkynylcyclobutanols with pyrazolidinones to access pyrazolo[1,2-a] indazoles bearing a quaternary carbon center was described. This method features high functional group tolerability and afforded pyrazolo[1,2-a] indazoles in moderate to good yield under mild conditions. (C) 2020 Elsevier Ltd. All rights reserved.