Table 2.
Data of absorption and fluorescence spectra of compounds 4a–i, 9a, and 10a.a
| Compound | UV–vis | Photoluminescence | ||||
| maxλabs, nm | ε, 103, M–1·cm–1 (λ, nm) |
λex, nm | maxλem, nm | Stokes shift, nm; eV |
Quantum yield Φflb | |
|
| ||||||
| 4a | 260; 302 | 30.3 ± 0.7 (260) |
300; 320 | 419 | 117; 1.15 | 0.22 ± 0.01 |
| 4b | 260; 302 | 38.3 ± 0.7 (260) |
300; 320 | 428 | 126; 1.21 | 0.23 ± 0.01 |
| 4c | 262; 302 | 22.2 ± 0.8 (262) |
300; 320 | 409 | 107; 1.07 | 0.16 ± 0.01 |
| 4d | 260; 301 | 35.1 ± 0.9 (260) |
300; 320 | 414 | 113; 1.12 | 0.15 ± 0.01 |
| 4e | 262; 301 | 22.7 ± 0.9 (262) |
300; 320 | 416 | 115; 1.14 | 0.18 ± 0.01 |
| 4f | 260; 302 | 27.6 ± 0.8 (260) |
300; 320 | 415 | 113; 1.12 | 0.20 ± 0.01 |
| 4g | 261; 300 | 41.5 ± 0.9 (261) |
300; 320 | 411 | 111; 1.12 | 0.20 ± 0.01 |
| 4h | 265; 305 | 32.4 ± 1.0 (265) |
300; 310 | 421 | 116; 1.12 | 0.23 ± 0.01 |
| 4i | 263; 301 | 26.2 ± 0.8 (263) |
300; 310 | 431 | 130; 1.24 | 0.09 ± 0.00 |
| 9a | 259; 303 | 40.0 ± 0.9 (261) |
305 | 433 | 130; 1.23 | 0.19 ± 0.01 |
| 10a | 261; 288 | 34.9 ± 0.5 (259) |
290 | 440 | 152; 1.49 | 0.11 ± 0.01 |
aIn EtOH solution, c = 1.0·10−5 mol·L−1. bQuantum yield determined relative to quinine sulfate standard in 0.5 M H2SO4 (Фf = 0.546).