Recent Advances in Transition-Metal-Free Aryl C-B Bond Formation

Arylboronic acids and their derivatives are widely used in organic synthesis. Conventional methods for their preparation require either reactive organometallic reagents or transition-metal-mediated processes. In recent years, transition-metal-free reactions for aryl C-B bond formation that obviate preformed organometallic reagents have gained interest and have developed rapidly. These new reactions have shown significant advantages for the preparation of functionalized molecules. In this review, an overview of the recent advances in transition-metal-free aromatic borylation reactions is provided. 1 Introduction 2 Transition-Metal-Free Transformations of C _Ar -N Bonds to C _Ar -B Bonds 3 Transition-Metal-Free Transformations of C _Ar -X Bonds to C _Ar -B Bonds 4 Transition-Metal-Free Transformations of C _Ar -H Bonds to C _Ar -B Bonds 5 Conclusion.