Alkylboronic Esters from Copper‐Catalyzed Borylation of Primary and Secondary Alkyl Halides and Pseudohalides

Easy access: An unprecedented copper-catalyzed cross-coupling reaction of the title compounds with diboron reagents is described (see scheme; Ts = 4-toluenesulfonyl). This reaction can be used to prepare both primary and secondary alkylboronic esters having diverse structures and functional groups. The resulting products would be difficult to access by other means.