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[12] Cyclic voltammograms for benzyltrifluoroborate 1a
showed a broad irreversible oxidation wave around
+0.67 V. Electrochemical data are shown in the Sup-
porting Information. Generation of a radical from the
precursor is strongly connected with their redox poten-
tials.
[13] Luminescent quenching experiments are summarized
in the Supporting Information. 1a and TEMPO
quenched efficiently emission of the Ir photoexcited
state *Ir-dF
ACHTUNGTNER(NUGN CF3). However luminescence from
*Ir-dF(CF3) was not quenched by 3a.
AHCTUNGTRENNUNG
1
[14] Monitoring the reaction mixture by H NMR revealed
that the reaction stopped on the way, presumably due
to deactivation of the Ir catalyst. In the reaction of 1m’
with 3b, further addition of the Ir catalyst after 12 h in-
creased the yield up to 50%.
3420
ꢀ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2012, 354, 3414 – 3420