Table 1. Screening of VLPC Catalysts in the Bromination of Naphthalene with NBS.
entrya | catalyst | % 3b | entrya | catalyst | % 3b |
---|---|---|---|---|---|
1 | none | 48 | 11 | methylene blue | 18 |
2 | acridine orange | 15 | 12 | methylene green | 77 |
3 | azure A | 31 | 13 | Nile blue A | 67 |
4 | brilliant cresyl blue | 27 | 14 | pyronin Y | 64 |
5 | brilliant green | 55 | 15 | rhodamine 6G | 61 |
6 | DDQ | 19 | 16 | rhodamine B | 60 |
7 | eosin Y | 0 | 17 | rose bengal | 87 |
8 | erythrosine B | 94 | 18 | safranin O | 54 |
9 | fluorescein | 58 | 19 | thionin | 71 |
10 | 9-mesityl-10-methylacridinium | 75 | 20 | [Ru(bpy)3]Cl2 | 0 |
Conditions: 0.25 mmol naphthalene, 0.25 mmol NBS, 0.0125 mmol catalyst, 3 mL MeCN, air, 20 °C, white light-emitting diode (LED), 24 h.
Gas chromatography (GC) yields calculated using adamantane as the internal standard.