Abstract
One electron oxidation of the tetragonal Cu(II) complex [Bu
4
N][LCuOH] at −80 °C generated the reactive intermediate LCuOH, which was shown to be a Cu(III) complex on the basis of spectroscopy and theory (L =
N
,
N
′-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide). The complex LCuOH reacts with dihydroanthracene to yield anthracene and the Cu(II) complex LCu(OH
2
). Kinetic studies showed that the reaction occurs via H-atom abstraction via a second-order rate law at high rates (cf.
k
= 1.1(1) M
−1
s
−1
at −80 °C, Δ
H
‡
= 5.4(2) kcal mol
−1
, Δ
S
‡
= −30(2) eu) and with very large kinetic isotope effects (cf.
k
H
/
k
D
= 44 at −70 °C). The findings suggest that a Cu(III)-OH moiety is a viable reactant in oxidation catalysis.