TY - JOUR
T1 - Unspecific Peroxygenase (UPO) can be Tuned for Oxygenation or Halogenation Activity by Controlling the Reaction pH
AU - Barber, Verity
AU - Mielke, Tamara
AU - Diaz-Rodriguez, Alba
AU - Cartwright, Jared
AU - Unsworth, William Paul
AU - Grogan, Gideon James
N1 - © 2024 The Authors
PY - 2024/5/17
Y1 - 2024/5/17
N2 - Unspecific Peroxygenases (UPOs) are increasingly significant enzymes for selective oxygenations as they are stable, highly active and catalyze their reactions at the expense of only hydrogen peroxide as the oxidant. Their structural similarity to chloroperoxidase (CPO) means that UPOs can also catalyze halogenation reactions based upon the generation of hypohalous acids from halide and H2O2. Here we show that the halogenation and oxygenation modes of a UPO can be stimulated at different pH values. Using simple aromatic compounds such as thymol, we show that, at a pH of 3.0 and 6.0, either brominated or oxygenated products respectively are produced. Preparative 100 mg scale transformations of substrates were performed with 60–72% isolated yields of brominated products obtained. A one-pot bromination-oxygenation cascade reaction on 4-ethylanisole, in which the pH was adjusted from 3.0 to 6.0 at the halfway stage, yielded sequentially brominated and oxygenated products 1-(3-bromo-4-methoxyphenyl)ethyl alcohol and 3-bromo-4-methoxy acetophenone with 82% combined conversion. These results identify UPOs as an unusual example of a biocatalyst that is tunable for entirely different chemical reactions, dependent upon the reaction conditions.
AB - Unspecific Peroxygenases (UPOs) are increasingly significant enzymes for selective oxygenations as they are stable, highly active and catalyze their reactions at the expense of only hydrogen peroxide as the oxidant. Their structural similarity to chloroperoxidase (CPO) means that UPOs can also catalyze halogenation reactions based upon the generation of hypohalous acids from halide and H2O2. Here we show that the halogenation and oxygenation modes of a UPO can be stimulated at different pH values. Using simple aromatic compounds such as thymol, we show that, at a pH of 3.0 and 6.0, either brominated or oxygenated products respectively are produced. Preparative 100 mg scale transformations of substrates were performed with 60–72% isolated yields of brominated products obtained. A one-pot bromination-oxygenation cascade reaction on 4-ethylanisole, in which the pH was adjusted from 3.0 to 6.0 at the halfway stage, yielded sequentially brominated and oxygenated products 1-(3-bromo-4-methoxyphenyl)ethyl alcohol and 3-bromo-4-methoxy acetophenone with 82% combined conversion. These results identify UPOs as an unusual example of a biocatalyst that is tunable for entirely different chemical reactions, dependent upon the reaction conditions.
U2 - 10.1002/chem.202401706
DO - 10.1002/chem.202401706
M3 - Article
SN - 0947-6539
JO - Chemistry : A European Journal
JF - Chemistry : A European Journal
M1 - e2024017
ER -