Table 2. Optimization of Reaction Conditions for Erythrosine B-Catalyzed Production of 1-Bromonaphthalene.
| entrya | equiv 2 | eryth B (mol %) | time (h) | solvent (mL) | additive (equiv) | % 3b |
|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 6 | MeCN (3) | none | 67 |
| 2 | 1.1 | 1 | 6 | MeCN (3) | none | 68 |
| 3 | 2 | 1 | 6 | MeCN (3) | none | 69 |
| 4 | 1 | 0 | 6 | MeCN (3) | none | 26 |
| 5 | 1 | 0.5 | 6 | MeCN (3) | none | 44 |
| 6 | 1 | 2 | 6 | MeCN (3) | none | 73 |
| 7 | 1 | 3 | 6 | MeCN (3) | none | 62 |
| 8 | 1 | 5 | 6 | MeCN (3) | none | 41 |
| 9 | 1 | 10 | 6 | MeCN (3) | none | 0 |
| 10 | 1 | 20 | 6 | MeCN (3) | none | 0 |
| 11 | 1 | 2 | 6 | MeOH (3) | none | 0 |
| 12 | 1 | 2 | 6 | DCM (3) | none | 12 |
| 13 | 1 | 2 | 6 | 4:1 MeCN/H2O (3) | none | 42 |
| 14 | 1 | 2 | 6 | MeCN (6) | none | 18 |
| 15 | 1 | 2 | 6 | MeCN (1.5) | none | 76 |
| 16 | 1 | 1 | 6 | MeCN (1.5) | none | 80 |
| 17 | 1 | 2 | 6 | MeCN (3) | oxone (1) | 78 |
| 18 | 1 | 2 | 2 | MeCN (3) | (NH4)2S2O8 (1) | 88 |
| 19 | 1.1 | 1 | 2 | MeCN (1.5) | (NH4)2S2O8(0.1) | 90 |
| 20 | 1.1 | 1 | 2 | MeCN (1.5) | (NH4)2S2O8 (0.02) | 78 |
a
Reaction conditions: 1 equiv = 0.25 mmol naphthalene.
b
GC yields calculated using adamantane as the internal standard.