Table 1.
| ||
---|---|---|
Entry | Conditionsa | Yield [%]b |
1 | 20 mol% B, 40 °C, CH2Cl2 | Trace |
2 | 20 mol% C, 40 °C, CH2Cl2 | 4 |
3 | 20 mol% A, 40 °C, CH2Cl2 | 94 |
4 | 10 mol% A, 40 °C, CH2Cl2 | 37 |
5 | 20 mol% A, 40 °C, CH3CN | 0 |
6 | 20 mol% A, 40 °C, THF | 50 |
General conditions: vinyl sulfone (1 equiv), nitrone (3 equiv), NaOt-Bu (20 mol%), solvent (0.10 M), 4 Å MS.
Yield of isolated products.