Cu-mediated vs. Cu-free selective borylation of aryl alkyl sulfones

A Cu-catalysed borylation of aryl alkyl sulfones was developed for the high yield synthesis of versatile arylboronic esters using a readily prepared NHC-Cu catalyst. In addition, the selective cleavage of either alkyl(C)-sulfonyl or aryl(C)-sulfonyl bonds of a cyclic sulfone via Cu-free or Cu-mediated processes generates the corresponding sulfinate salts, which can be further derivatised to provide sulfonyl-containing boronate esters, such as sulfones and sulfonyl fluorides.

Automated summary

A Cu-catalysed borylation reaction can achieve high-yield synthesis of arylboronic esters from aryl alkyl sulfones, while selective cleavage of cyclic sulfones can be achieved through Cu-mediated or Cu-free processes to prepare sulfonyl-containing boronate esters.