Table 2.
| |||||
---|---|---|---|---|---|
entry | substrate | product | catalystb | drc | yield (%)d |
1 | A | >25:1 (20:1) | 76 | ||
2 | (±)-5a | A | 8:1 (5:1) | 78 | |
3 | (±)-5a | Be | >25:1 (5:1) | 42 | |
4 |
(+)-5a 92% ee |
B | 8:1 (7:1) 86% ee |
58 | |
5 | B | 14:1 (5:1) | 60 | ||
6 |
(−)-5d 87% ee |
A | >25:1 (10:1) 91% ee |
75 | |
7 | C | 15:1 (3:1) | 45 | ||
8 | A | 25:1 (12:1) | 68 | ||
9 | (±)-5b | A | 22:1 (8:1) | 63 | |
10 | (±)-5b | Be | 7:1 (3:1) | 56 | |
11 |
(+)-5b 88% ee |
B | >25:1 (10:1) 92% ee |
56 | |
12 | B | 11:1 (12:1) | 79 | ||
13 | (±)-5e | B | 10:1 (7:1) | 47 | |
14 | A | 15:1 (5:1) | 35 |
Conditions: Reactions were conducted on a 0.25 mmol scale using 1.0 equiv of substrate, 1.2 equiv of ArCl, 2.4 equiv of NaOtBu, catalyst (4 mol % [Pd]), toluene (0.25 M), 100 °C.
Catalyst A: Pd(OAc)2 (4 mol %), Cy4Dpe-Phos 15 (4 mol %). Catalyst B: Pd2(dba)3 (2 mol % complex), PCy3•HBF4 (4 mol %). Catalyst C: Pd2(dba)3 (2 mol % complex), X-Phos 14 (8 mol %).
Diastereomeric ratios are reported for the isolated products. Diastereomeric ratios in parentheses were observed in crude reaction mixtures.
Isolated yield (average of two experiments).
The reaction was conducted using 8 mol % PCy3•HBF4.