Table 2. Fluorescence Quantum Yields (ϕF), Fluorescence Decay Times (τ1 and τ2), and Pre-exponential Factors (a1 and a2), for the 3,6-dtb-DPBF Derivatives in MeCN/Water Mixtures with Oxygen, without Oxygen (N2-saturated), and with Oxygen Saturation (O2 sat.) at 293 K, Obtained with λexc = 261 nm and λem = 470 nm.
| compound | conditions | ϕF | τ1 (ns) | τ2 (ns) | a1 (% C1) | a2 (% C2) | χ2 |
|---|---|---|---|---|---|---|---|
| 3,6-dtb-DPBF (fw = 75%) | N2 sat. | 0.104 | 1.02 | 29.45 | 0.045 (0.2) | 0.955 (99.8) | 1.03 |
| air | 0.120 | 0.90 | 29.49 | 0.023 (0.1) | 0.977 (99.9) | 1.11 | |
| O2 sat. | 0.053 | 1.45 | 27.39 | 0.231 (2) | 0.769 (98) | 1.02 | |
| 3,6-dtb-DPBFMe (fw = 60%) | N2 sat. | 0.139 | 2.46 | 32.83 | 0.099 (1) | 0.901 (99) | 1.05 |
| air | 0.171 | 2.55 | 33.02 | 0.101 (1) | 0.899 (99) | 1.05 | |
| O2 sat. | 0.116 | 2.55 | 32.81 | 0.150 (1) | 0.850 (99) | 1.03 | |
| 3,6-dtb-DPBF(Me)2 (fw = 80%) | N2 sat. | 0.196 | 3.85 | 36.87 | 0.134 (2) | 0.866 (98) | 1.05 |
| air | 0.216 | 3.78 | 37.16 | 0.146 (2) | 0.854 (98) | 1.09 | |
| O2 sat. | 0.117 | 2.96 | 33.48 | 0.264 (3) | 0.736 (97) | 0.99 |