Inorganic Chemistry
Communication
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(14) Abbreviations: TQA = tris(quinolyl-2-methyl)amine), Bn-
TPEN = N-benzyl-N,N′,N′-tris(2-pyridylmethyl)-1,2-diaminoethane),
CAN = cerium(IV) ammonium nitrate, NMR = nuclear magnetic
resonance spectroscopy, EPR = electron paramagnetic resonance
spectroscopy, TON = turnover number, Me2phen = 4,7-dimethyl-1,10-
phenanthroline, Ph2phen = 4,7-diphenyl-1,10-phenanthroline, bpy =
2,2′-bipyridyl, and 5-Clphen = 5-Chloro-1,10-phenanthroline.
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(22) The names of brominated products are based on the numbers
used for substrates, as shown in Table S1.
(23) The control reactions were performed as follows (Figure S8): (a)
The reaction of TMeOB with PhIO in the presence of Sc(OTf)3 and
TBABr without [(Bn-TPEN)MnII]2+ resulted in no bromination, as
confirmed by 1H NMR. (b) The reaction of TMeOB with [(Bn-TPEN)
MnII]2+ in the presence of Sc(OTf)3 and TBABr without PhIO resulted
1
in no bromination as confirmed by H NMR. (c)The reaction of
TMeOB with [(Bn-TPEN)MnII]2+, PhIO and TBABr in the absence of
Sc(OTf)3 resulted in no bromination as confirmed 1H NMR.
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(30) It should be noted that no formation of TMeOB•+ was observed
in the reaction of 1 with TMeOB in the presence of TBABr (Figure
S18), indicating that ET from TMeOB to 1 is the rate-determining step.
(31) If another molecule of Mn(IV)−oxo was involved in the reaction,
the Mn(III) product would be obtained. However, the EPR
measurements after the catalytic reaction showed that the Mn(II)
complex was the product, supporting the proposed mechanism (step
d).
E
Inorg. Chem. XXXX, XXX, XXX−XXX