Frontier molecular orbital analysis of Cu(n)-O(2) reactivity.
Frontier molecular orbital (FMO) theory coupled with density functional calculations has been applied to investigate the chemical reactivity of three key bioinorganic Cu(n)-O(2) complexes, the mononuclear end-on hydroperoxo-Cu(II), the side-on bridged mu-eta(2):eta(2)-O(2)(2-) Cu(II)(2) dimer and the bis-mu-oxo Cu(III)(2) dimer. Two acceptor orbitals (sigma* and pi*) of each complex and two types of donating substrates (sigma-substrate, phosphine; pi-substrate, alkylbenzene) are considered in the electrophilic attack mechanism. The angular dependences of different reaction pathways are determined using FMO theory and the angular overlap model. Including steric effects, the sigma*/sigma and pi*/pi pathways are found more reactive than the corresponding cross sigma*/pi and pi*/sigma pathways which have poor donor-acceptor orbital overlaps in the sterically constrained substrate access region.
Chen
Peng
P
Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
Solomon
Edward I
EI
D003300:Copper / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry; D008958:Models, Molecular; D010100:Oxygen / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry
D006841:Hydrocarbons, Aromatic; D010720:Phosphines; D003300:Copper; C044646:phosphine; D010100:Oxygen