Table 1.
| |||
---|---|---|---|
entry | acid | ester (yield)a | acid (yield, dr)a |
1 | Ac2O | 70a (82%)b | -- |
2 | 70b (83%) | -- | |
3 | 70c (73%) | 71a (80%, 6:1)c | |
4 | 70d (93%) | -- | |
5 | 70e (63%) | -- | |
6 | 70f (74%) | -- | |
7 | 70g (54%) | -- | |
8 | 70h (87%) | 71b (57%, 6.6:1.1:1)c |
Isolated yields.
Conditions: Ac2O, NEt3, DMAP (10 mol %), CH2Cl2, rt.
Determined by 1H NMR analysis of crude mixtures.