Entry | Nu | Conditions | Yield/% | ||
|
|
| 5-Boc | 5-H | 4 |
1 2 3 4 | A A B B | 0˚C-RT, ON −78˚C, ON 0˚C, 1.5 h −78˚C, 2 h |
27
24 | 58 60 97 9 | 38
15 |