Synthesis and characterization of carboxylate-rich complexes having the [Fe2(mu-OH)2(mu-O2CR)]3+ and [Fe2(mu-O)(mu-O2CR)]3+ cores of O2-dependent diiron enzymes.
The {Fe2(mu-OH)2(mu-O2CR)}3+ and {Fe2(mu-O)(mu-O2CR)}3+ cores of the carboxylate-bridged diiron(III) centers in the enzyme active sites were reproduced by small molecule model complexes that were prepared through direct oxygenation of the mononuclear iron(II) complexes. Upon oxygenation of [Fe(O2CArTol)2(Hdmpz)2], where -O2CArTol is 2,6-di(p-tolyl)benzoate and Hdmpz is 3,5-dimethylpyrazole, [Fe2(mu-OH)2(mu-O2CArTol)(O2CArTol)3(OH2)(Hdmpz)2] was generated and characterized to share close physical properties with sMMOHox, including delta = 0.45 (2) mm/s, DeltaEQ = 1.21 (2) mm/s, and J = -7.2 (2) cm-1. The compound [Fe2(mu-O)(mu-O2CAr4-FPh)(O2CAr4-FPh)3(Hdmpz)3], where -O2CAr4-FPh is 2,6-di(4-fluorophenyl)benzoate, with delta = 0.51 (2) mm/s, DeltaEQ = 1.26 (2) mm/s, and J = -117.4 (1) cm-1, was isolated as the oxygenation product of [Fe(O2CAr4-FPh)2(Hdmpz)2].
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Sungho
S
Yoon
Stephen J
SJ
Lippard
D001665:Binding Sites; D040761:Biomimetic Materials / Q000138:chemical synthesis / Q000737:chemistry; D002264:Carboxylic Acids / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005290:Ferric Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D010105:Oxygenases / Q000737:chemistry*; D012264:Ribonucleotide Reductases / Q000737:chemistry*; D013230:Stearoyl-CoA Desaturase / Q000737:chemistry*
D002264:Carboxylic Acids; D005290:Ferric Compounds; D005296:Ferrous Compounds; D010105:Oxygenases; C021555:methane monooxygenase; D013230:Stearoyl-CoA Desaturase; D012264:Ribonucleotide Reductases; C108427:ribonucleotide reductase R2 subunit; D010100:Oxygen