The reactions of ·CH3 and ·CH2C(CH3)2OH with Cu(II)(GGG), GGG=glycylglycylglycine, in aqueous solutions were studied and compared with the analogous process for Cu(II)(glycine)2. The mechanism involves the following steps:Cu(II)L+·R→LCu(III)R·R+LCu(II)-R→Cu(II)L+R 2LCu(III)-R→(LCu(III)-R′)The heterolysis of the Cu(III)-CH3 bond for (Gly)2Cu(III)-CH3 yields methane and Cu(III)(Gly)2+ whereas that for (GGG)Cu(III)-CH3 yields Cu(I)(GGG) and methanol. The LCu(III)-CH2C(CH3)2OH complexes decompose viaLCu(III)-CH2C(CH3)2OH→Cu(I)L+HOCH 2C(CH3)2OHfollowed byCu(I)L+LCu(III)-CH2C(CH3)2OH→Cu(II) L+LCu(II)-CH2C(CH3)2OHLCu(II)-CH 2C(CH3)2OH→Cu(II)L+CH2=C (CH3)2+OH-.The complex (GGG)Cu(III)-CH3 decomposes slowly, k=0.0035 s-1. Thus if analogous complexes are formed in biological systems they might react with other substrates present in the system yielding products which are deleterious to living species.
|Number of pages||9|
|Journal||Inorganica Chimica Acta|
|State||Published - 15 Nov 2002|
Bibliographical noteFunding Information:
This study was supported in part by a grant from the Budgeting and Planning Committee of The Council of Higher Education and the Israel Atomic Energy Commission. D.M. wishes to thank the Alexander von Humboldt Foundation for support and Mrs. Irene Evens for her ongoing interest and support.
- Alkyl radicals
- Biological ligands complexes
- Copper complexes