Table 1.
Exploration of copper-mediated radioiodination with the addition of acids to neutralize strong basic conditions.
| |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Experimenta | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|
| |||||||||
| Precursor (μmol) | 0.64 | 0.64 | 0.64 | 0.64 | 0.64 | 0.64 | 0.64 | 0.32 | 0.32 |
| [Cu] (μmol) | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 | 2.5 |
| NaOH (μmol) | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 | 5 |
| PPTS (μmol) | / | 5 | 10 | 20 | / | / | / | 20 | / |
| TsOH·H2O (μmol) | / | / | / | / | 5 | 10 | 20 | / | 20 |
| RCC (%) | 44 | 73 | 79 | 98 | 72 | 79 | 99 | 13 | 5 |
Note:
a.
Reaction condition: [123I]NaI (15 μCi), [Cu]: Cu(OTf)2(Py)4, DMSO (400 μL) and water (50 μL) as the reaction solvents, 110 °C/10 min in air atmosphere. RCC was determined by radio-HPLC.