Cu‐Catalyzed Intramolecular Borylation‐Cross Coupling Reaction of Unactivated Alkenes to Borylated Indolines

Abstract Cu‐catalyzed intramolecular borylation‐cross coupling reaction of alkenes was developed. Racemic and chiral borylated indolines were achieved by borylation‐cross coupling of alkenes with B 2 pin 2 via simultaneous construction of C−C and C−B bonds by Cu/phosphine ligand system. With CuOAc and DPPE ligand, a series of 3‐substituted borylated indoline derivatives were concisely synthesized in good to excellent yields in short time under mild conditions. Asymmetric synthesis was investigated by ligand screening, and the chiral 3‐substituted borylated indoline was obtained in 80% yield and 80:20 er with ( R , R)‐ Me‐Duphos. Application of 3‐substituted borylated indolines has been demonstrated by a gram scale synthesis and further functionalization.