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Title: Dual oxidase/oxygenase reactivity and resonance Raman spectra of {Cu 3 O 2 } moiety with perfluoro- t -butoxide ligands
A Cu( i ) fully fluorinated O-donor monodentate alkoxide complex, K[Cu(OC 4 F 9 ) 2 ], was previously shown to form a trinuclear copper–dioxygen species with a {Cu 3 (μ 3 -O) 2 } core, T OC4F9 , upon reactivity with O 2 at low temperature. Herein is reported a significantly expanded kinetic and mechanistic study of T OC4F9 formation using stopped-flow spectroscopy. The T OC4F9 complex performs catalytic oxidase conversion of hydroquinone (H 2 Q) to benzoquinone (Q). T OC4F9 also demonstrated hydroxylation of 2,4-di- tert -butylphenolate (DBP) to catecholate, making T OC4F9 the first trinuclear species to perform tyrosinase (both monooxygenase and oxidase) chemistry. Resonance Raman spectra were also obtained for T OC4F9 , to our knowledge, the first such spectra for any T species. The mechanism and substrate reactivity of T OC4F9 are compared to those of its bidentate counterpart, T pinF , formed from K[Cu(pin F )(PR 3 )]. The monodentate derivative has both faster initial formation and more diverse substrate reactivity.
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Dalton Transactions
Page Range or eLocation-ID:
6899 to 6909
Sponsoring Org:
National Science Foundation
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