Table 1. pH effects on the k obs values for the decay of the labile CS2 donors 1, 2, and 5. Conditions: 37 °C in 50 mM phosphate buffer adjusted to 154 mM ionic strength with NaCl except where noted.
| pH |
k
obs (in 10–3 s–1) for various donors |
||
| ImDTC– (5) | DIDTC– (1) | MorDTC– (2) | |
| 2.0 | 370 | ||
| 3.0 | 360 | ||
| 4.0 a | 320 ± 1 | ||
| 5.5 a | 48 800 ± 65 | 64.0 ± 0.1 | |
| 6.5 | 7990 ± 4 | 15.2 ± 0.3 | 0.36 |
| 6.8 | 9.6 ± 0.3 | 0.18 | |
| 7.0 | 6.8 ± 0.2 | 0.11 | |
| 7.4 | 775 ± 0.4 | 3.5 ± 0.1 | 0.043 ± 0.001 |
| 7.6 | 2.35 ± 0.08 | 0.025 | |
| 7.8 | 1.56 ± 0.04 | 0.015 | |
| 10.3 b | 3.5 ± 0.02 | ||
| 11.2 c | 0.08 | ||
aAcetate buffer at μ = 132 mM.
bCarbonate buffer.
c1.5 mM NaOH.