Copper-dioxygen chemistry and modeling the Fe-Cu center in cytochrome c oxidase
نویسندگان
چکیده
The copper(1) complex [(TMPA)Cu(RCN)]+ (1) binds 0 2 forming [{ (TMPA)Cu}2(02)]2+ (2), with trans-y-1, 2 peroxo-coordination. Ligands with quinolyl groups substituting for the pyridyl donors in TMPA cause dramatic changes in the course of reaction, in one case stabilizing a CdO2 1:l adduct [(BQPA)Cu(02)]+ (6 ) . The kinetics/thermodynamics are compared. Reaction of 1 with (F 8-TPP)Fe(II)pip2 (8) and 0 2 yields the p-0x0 species [(Fg-TPP)Fem-O-Cun(TMPA)]+ (9); this reversibly protonates giving p-hydroxo bridged [(Fg-TPP)Fe-(OH)-Cu(TMPA)]2+ (12). The novel NMR properties of 9 are described. These complexes are discussed in terms of their model 02-chemistry in hemocyanins or cytochrome c oxidase.
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