No abstract

A tyrosinase‐mediated arylation towards a variety of different building blocks is presented. Utilizing phenol or simple substituted phenols, the corresponding quinones are synthesized in a two‐step procedure by an enzyme‐catalyzed oxidation (tyrosinase from Aspergillus oryzae). The activated intermediates undergo a 1,4‐addition with selected β‐dicarbonyl compounds. Starting from phenol, yields of isolated product for the hydroxylation‐oxidation‐arylation sequence range from 43–77 %, whereas substituted acceptors provided 9–55 %, only. Different substitution patterns on phenol revealed that electron donating functionalities are preferentially accepted to electron withdrawing ones, whereas ortho‐substituted phenols are not accepted at all.