Table 2.
Pd-catalyzed synthesis of substituted isoxazolidines[a]
 | ||||
|---|---|---|---|---|
| Entry | Substrate | Isoxazolidine | dr[b] | Yield[b] |
| 1 |  |
 |
- | 85% |
| 2 |  |
 |
>20:1 (5:1) |
56% |
| 3 | 5 |  |
3:1 (3:1) |
70% |
| 4 | 5 |  |
>20:1 (3:1) |
57% |
| 5 |  |
 |
3:1 (3:1) |
77% |
| 6 | 6 |  |
3:1 (3:1) |
78% |
| 7 |  |
 |
3:1 (3:1) |
61% |
| 8 |  |
 |
>20:1 (10:1) |
82% |
| 9 | 8 |  |
>20:1 (10:1) |
85% |
| 10 |  |
 |
19:1 (9:1) |
94% |
| 11 | 9 |  |
>20:1 (9:1) |
89% |
| 12[d] |  |
 |
>20:1 (>20:1) |
78% |
| 13[d] | 10 |  |
>20:1 (>20:1) |
69% |
[a]
Conditions: 1.0 equiv substrate, 1.2 equiv ArBr, 1.2 equiv NaOtBu, 2 mol % Pd(OAc)2, 2 mol % DPE-Phos, THF (0.125 M), 65 °C.
[b]
dr = diastereomeric ratio of isolated material. Numbers in parentheses are the observed diastereomeric ratios for the crude reaction mixture.
[c]
Yields represent average isolated yields for two or more experiments.
[d]
The reaction was conducted at 110 °C in toluene solvent with Pd2(dba)3 (1 mol %) used in place of Pd(OAc)2.