Table 1.
Counter-ion content after each exchange
| Solution | Counter-ion [mol%] | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Repetition | |||||||||
| 1 | 2 | 3 | 4 | ||||||
| Cl− | TFA− | Cl− | TFA− | Cl− | TFA− | Cl− | TFA− | ||
| A | 0.1 M HCl (0.365%) | 87 | 13 | 93 | 7 | 94 | 6 | 96 | 4 |
| B | 0.5% HCl in acetonitrile | 98 | 2 | 98 | 2 | 98 | 2 | 98 | 2 |
| C | 2.0% HCl in dichloromethane | 90 | 10 | 92 | 8 | 94 | 6 | 96 | 4 |
| D | 1.4% HCl in ethyl acetate | 77 | 23 | 85 | 15 | 86 | 14 | 98 | 2 |
| E | 1.5% HCl in 2-propanol | 97 | 3 | 98 | 2 | 99 | 1 | 99 | 1 |
| F | 2.5% HCl in methanol | 98 | 2 | 99 | 1 | 99 | 1 | 99 | 1 |
| G | 1.5% HCl in n-butanol | 97 | 3 | 98 | 2 | 99 | 1 | 99 | 1 |
| H | 1.5% HCl in tert-butanol | 98 | 2 | 99 | 1 | 99 | 1 | 99 | 1 |
Bold values indicate efficiency of proposed method after just one repetition