Herein, we report a Rh(III)‐catalyzed 1,3‐dienylation of isoquinolin‐1(2H)‐ones through C−H activation. The present reaction enables the preparation of 3‐(buta‐1,3‐dien‐2‐yl)isoquinolin‐1(2H)‐ones through the direct cross‐coupling reaction of readily available isoquinolin‐1(2H)‐ones with methylenecyclopropanes, while tolerating many sensitive functional groups. Therefore, this method provides an efficient and convenient approach for modification of interesting molecules.magnified image

Herein, we report a Palladium(0)‐catalyzed C4 site‐selective C−H difluoroalkylation of isoquinolin‐1(2H)‐ones through a radical pathway. The present reaction enables the preparation of 2,2‐difluoro‐2‐(1‐oxo‐1,2‐dihydroisoquinolin‐4‐yl)acetates/acetamides through the direct cross‐coupling reaction of readily available isoquinolin‐1(2H)‐ones with 2‐bromo‐2,2‐difluoroacetates or 2‐bromo‐2,2‐difluoroacetamides. Therefore, this method provides an efficient and convenient approach to install a difluoroacetate or a difluoroacetamide moiety into bioactive molecules. Bioassay results showed that introduction of these difluorinated groups at C4 position was beneficial to improve their antiviral activity and compound 5 ab was found to exhibit similar antiviral activity with commercial Ningnanmycin.

Under rhodium(III) catalysis, substituted N‐methoxycycloalkene‐1‐carboxamides successfully reacted with aryl boronic acid pinacol esters to provide 3,4‐cycloalkaquinolin‐2(1H)‐ones via direct functionalization of the β‐alkenyl C−H bond and form C−C/C−N bond in one pot. The gram‐scale synthesis of the title compound demonstrated the great synthetic utility of this methodology.magnified image