Table 3.
| ||||
---|---|---|---|---|
entry | R | product | isolated yielda | dr (anti:syn)b |
1 | i-Pr | (−)-6a | 83 (80)c | 9:1d |
2 | 4-BrPh | 6b | 57 | 3:1 |
3 | n-Pent | 6c | 82 | 2:1 |
4 | t-Bu | 6d | 22 | 11:1 |
5 | 6e R=Ph | 57 | 3:1 | |
6 | 6f R=n-Bu | 60 | 3:1 | |
7 | (−)-6g | 62 | 8:1 | |
8 | (+)-6h | 62 | 4:1 |
Average of 2 runs at 0.3 mmol.
Diastereomeric ratio determined by GC of the crude reaction after workup.
Average of 2 runs at 10 mmol.
Diastereomeric ratio determined by 1H NMR of the crude reaction after workup.