K. Tsuchiya, E. Ito, S. Yagai, A. Kitamura, T. Karatsu
FULL PAPER
Figure 6 leads to bond dissociation of the Ir–N1 or Ir–N3
bond, and this produces Λ-fac and ∆-fac isomers, respec-
tively, as shown in Figure 4.
Acknowledgments
The authors thank Prof. Hugh D. Burrows (University of Coinbra)
and Prof. Henrik Ottosson (Uppsala University) for their dis-
cussions. This work was supported by Grants-in-Aids for Scientific
Research from the Ministry of Education, Culture, Sports, Science
and Technology (MEXT) (No. 20550056).
The shape of the potential energy surface controls the
direction of bond elongation (Ir–N1 or Ir–N3) and finally
the ee values. Calculated potential energies for bond-elon-
gated structures were 2.8 kcalmol–1 higher (Ir–N1 2.80 Å)
and 0.5 kcalmol–1 lower (Ir–N3 2.80 Å) than the energy of
the fully optimized structure. These single-point energy cal-
culation results do not fit the results of the ee values, be-
cause it is preferable to proceed to the B route to give the
fac-∆ isomer. More calculations for the whole potential en-
ergy surface are necessary to obtain, for example, activation
energies in the reaction coordinate. Those detailed calcula-
tions, including TD-DFT calculations, are ongoing in our
group.
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Experimental Section
fac-Ir(ppz)3:[7b] 1H NMR (396 MHz, CDCl3): δ = 7.97 (d, J =
2.7 Hz, 3 H), 7.19 (dd, J = 7.8, 1.1 Hz, 3 H), 6.978 (d, J = 2.1 Hz,
3 H), 6.914 (ddd, J = 7.8, 7.1, 1.6 Hz, 3 H), 6.843 (dd, J = 7.5,
1.5 Hz, 3 H), 6.776 (ddd, J = 7.4, 7.2, 1.2 Hz, 3 H), 6.376 (dd, J =
2.4, 2.4 Hz, 3 H) ppm. 13C NMR (99.45 MHz, CDCl3): δ = 144.2,
139.8, 137.5, 136.7, 125.8, 124.9, 120.4, 110.8, 106.7 ppm. MS
(FAB): m/z = 622.00.
mer-Ir(ppz)3:[7b] 1H NMR (396 MHz, CDCl3): δ = 8.00 (dd, J = [13] C. Schaffner-Hamann, A. von Zelewsky, A. Barbieri, F. Barig-
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2.4, 0.5 Hz, 1 H), 7.95 (dd, J = 2.9, 0.7 Hz, 1 H), 7.91 (dd, J = 2.6,
0.7 Hz, 1 H), 7.281 (dd, J = 7.7, 0.8 Hz, 1 H), 7.24 (dd, J = 10.0,
0.8 Hz, 1 H), 7.19 (dd, J = 13.7,0.8 Hz, 1 H), 7.15 (d, J = 1.2 Hz,
1 H), 7.05 (dd, J = 7.1, 1.5 Hz, 1 H), 6.99–6.85 (m, 6 H) 6.81–6.75
(m, 3 H), 6.49 (dd, J = 7.5, 1.4 Hz, 1 H), 6.35–6.34 (m, 2 H), 6.30
(dd, J = 2.8, 2.2 Hz, 1 H) ppm. 13C NMR (99.45 MHz, CDCl3): δ
= 152.3, 151.4, 145.9, 144.6, 142.9, 140.1, 139.9, 139.3, 139.0, 135.8,
135.2, 132.6, 126.3, 126.3, 126.0, 125.9, 124.8, 122.4, 121.9, 120.0,
111.5, 110.9, 110.9, 107.3, 107.3, 107.0 ppm. MS (FAB): m/z =
621.89.
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