Synthesis of CF2H-containing isoquinoline-1,3-diones through metal-free, visible-light and air-promoted radical difluoromethylation/cyclization of N-benzamides

Abstract

A novel visible-light and air-promoted direct radical difluoromethylation of N-benzamides for synthesis of CF 2 H-containing isoquinoline-1,3-diones has been achieved, which represents the first metal-free catalytic synthesis of CF 2 H-containing isoquinoline-1,3-diones. This protocol provides an efficient strategy for the synthesis of a variety of CF 2 H-containing isoquinoline-1,3-diones with commercially available NaSO 2 CF 2 H. The reaction features mild reaction conditions, metal-free, air oxidation and additives free. • An efficient metal-free and visible-light-promoted radical difluoromethylation of N-benzamides is developed. • CF 2 H-containing isoquinoline-1,3-diones are constructed readily with commercially available NaSO 2 CF 2 H. • The important potential pharmaceutical N-OH substituted isoquinoline-1,3-dione has been successfully synthesized. • Mechanistic studies indicate that the O 2 in air was the oxidant in this reaction system. • The reaction was performed in mild reaction conditions and additives free.