Table 2. Summary of the UV-vis absorption spectroscopy, cyclic voltammetry, and DFT calculations of pentalenes 3 .
| Compound | λ max [nm] (ε max a [×104 L mol–1 cm–1]) | E onset ox b [eV] | E onset red b [eV] | E HOMO,CV c [eV] (E HOMO,cal d [eV]) | E LUMO,CV c [eV] (E LUMO,cal d [eV]) | E g,CV e [eV] (E g,cal f [eV]) |
| 3ba | 444 (1.0) | 0.82 | –1.69 | –5.62 (–5.31) | –3.11 (–2.36) | 2.51 (2.95) |
| 3bb | 478 (1.7) | 0.80 | –1.72 | –5.60 (–5.31) | –3.08 (–2.30) | 2.52 (3.01) |
| 3db | 500 (1.9) | 0.71 | –1.78 | –5.51 (–5.16) | –3.02 (–2.26) | 2.48 (2.90) |
| 3ea | 613 (0.24) | 0.05 | –1.82 | –4.85 (–4.65) | –2.98 (–2.12) | 1.87 (2.52) |
| 3bd | 455 (1.5) | 1.08 | –1.33 | –5.88 (–5.79) | –3.47 (–2.92) | 2.41 (2.87) |
| 3ed | 676 (0.28) | 0.16 | –1.42 | –4.96 (–5.00) | –3.38 (–2.68) | 1.58 (2.32) |
| 3fa | 600 (0.045) | 0.48 | –1.60 | –5.28 (–5.00) | –3.20 (–2.45) | 2.08 (2.55) |
| 3bf | 434 (0.68) | 0.91 | –1.59 | –5.71 (–5.50) | –3.21 (–2.51) | 2.50 (2.99) |
| 3ff | 595 (0.053) | 0.61 | –1.50 | –5.41 (–5.18) | –3.30 (–2.61) | 2.11 (2.58) |
aMeasured in CH2Cl2 (1.0 × 10–4 M).
bCV measured with Bu4NPF6 in CH2Cl2 (1.0 × 10–3 M) with a scan rate of 100 mV s–1 under argon containing Ag/Ag+ as the reference electrode, Pt as the working electrode, and Pt wire as the counter electrode. Values are against Fc/Fc+.
c E HOMO(LUMO),CV = –(Eonsetox(red) + 4.8).
dValues calculated at the B3LYP/6-31G(d) level of theory.
e E g,CV = E LUMO,CV – E HOMO,CV.
f E g,cal = E LUMO,cal – E HOMO,cal.