Copper-Catalyzed Chlorination of Arylboronic Acids

Significance

The first transition-metal-catalyzed aryl chlorodeboronation using NCS as electrophilic chlorine source has been described. The ­reaction proceeds under mild conditions tolerating a broad variety of sensitive functionalities. Moreover, the method is highly general and can be efficiently applied to both electron-rich and electron-deficient arylboronic acids. The latter are especially difficult to access with the conventional chloro­deboronation reactions.