Authors: McCarthy , C; Losada‐Garcia , N; Palomo, J.M.

Article.
ChemistrySelect. vol: 5. Issue:25. page: 7492-7496
Date: july-7. 2020.
Doi: doi.org/10.1002/slct.202002110

Abstract:
Selective hydroxylation of different phenylboronic acids to phenols was successfully carried out by using Cu nanoparticles‐enzyme hybrid catalysts in water and room temperature. Different Cu‐enzyme hybrids containing Cu(II), Cu(I) and Cu(0) nanoparticles species respectively were tested on the monohydroxylation of phenylboronic acid under these mild conditions being hybrids containing Cu(0)NPs the best catalysts, with total selectivity and formation of phenol as unique product. Also, the addition of hydrogen peroxide or the increase of reaction temperature were tested but did not improved these results. The substrate scope was also demonstrated and the Cu(0)NPs hybrid showed excellent results in the monohydroxylation of different o‐, m‐, p‐ substituted phenylboronic acid with final yields >95 %. This catalyst showed excellent recyclability after 5 cycles of use.