TY - JOUR
T1 - Copper-Mediated Hydroxylation of an Arene
T2 - Model System for the Action of Copper Monooxygenases. Structures of a Binuclear Cu(I) Complex and Its Oxygenated Product
AU - Karlin, Kenneth D.
AU - Hayes, Jon C.
AU - Gultneh, Yilma
AU - Cruse, Richard W.
AU - McKown, Jeffrey W.
AU - Hutchinson, John P.
AU - Zubieta, Jon
PY - 1984
Y1 - 1984
N2 - A chemical system possessing features that mimic the structures and reactivity of the active sites of the copper oxygen carrier hemocyanin (Hc) and the monooxygenase tyrosinase (Tyr) is presented. When a dinuclear 3-coordinate Cu(I) complex, II, of a binucleating ligand, I, where the two tridentate nitrogen donor groups are separated by a m-xylyl bridge is reacted with dioxygen, the specific hydroxylation of the aromatic ring occurs in high yield (<90%). This produces a binuclear pentacoordinate phenolato and hydroxo doubly bridged Cu(II) complex, IIIB. Manometric and mass spectrometric measurements utilizing isotopically labeled 18O2 show that the phenolate and hydroxy oxygen atoms in IIIB are derived from dioxygen, making this reaction an excellent biomimic for the action of the copper monooxygenases. Removal of the copper ions from IIIB gives a new phenol, IV, completing the sequence of the copper-mediated hydroxylation of an aromatic ring, I → IV. Crystallographic studies have been completed on both II and III. II crystallizes in the triclinic space group [formula omitted] with Z = 2 and a = 11.264 (3) Å, b = 11.448 (3) Å, c = 15.722 (4) Å, α = 95.72 (2)°, β = 102.05°, γ = 94.77°. IIIB crystallizes in the monoclinic space group P21/c, Z = 4, with a = 18.221 (3) Å, b = 13.323 (3) Å, c = 18.643 (4) Å, and β = 102.39 (2)°. The structural features of these complexes are compared to those of other related compounds and to the active sites of the copper proteins. The biological relevance of the monooxygenase model system is also discussed.
AB - A chemical system possessing features that mimic the structures and reactivity of the active sites of the copper oxygen carrier hemocyanin (Hc) and the monooxygenase tyrosinase (Tyr) is presented. When a dinuclear 3-coordinate Cu(I) complex, II, of a binucleating ligand, I, where the two tridentate nitrogen donor groups are separated by a m-xylyl bridge is reacted with dioxygen, the specific hydroxylation of the aromatic ring occurs in high yield (<90%). This produces a binuclear pentacoordinate phenolato and hydroxo doubly bridged Cu(II) complex, IIIB. Manometric and mass spectrometric measurements utilizing isotopically labeled 18O2 show that the phenolate and hydroxy oxygen atoms in IIIB are derived from dioxygen, making this reaction an excellent biomimic for the action of the copper monooxygenases. Removal of the copper ions from IIIB gives a new phenol, IV, completing the sequence of the copper-mediated hydroxylation of an aromatic ring, I → IV. Crystallographic studies have been completed on both II and III. II crystallizes in the triclinic space group [formula omitted] with Z = 2 and a = 11.264 (3) Å, b = 11.448 (3) Å, c = 15.722 (4) Å, α = 95.72 (2)°, β = 102.05°, γ = 94.77°. IIIB crystallizes in the monoclinic space group P21/c, Z = 4, with a = 18.221 (3) Å, b = 13.323 (3) Å, c = 18.643 (4) Å, and β = 102.39 (2)°. The structural features of these complexes are compared to those of other related compounds and to the active sites of the copper proteins. The biological relevance of the monooxygenase model system is also discussed.
UR - http://www.scopus.com/inward/record.url?scp=0001726115&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0001726115&partnerID=8YFLogxK
U2 - 10.1021/ja00319a036
DO - 10.1021/ja00319a036
M3 - Article
AN - SCOPUS:0001726115
SN - 0002-7863
VL - 106
SP - 2121
EP - 2128
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 7
ER -