Table 1.
Preparative results for the addition-cyclisation of 4 with 1
 | |||||
|---|---|---|---|---|---|
| Entry (acid4) | Ar | Conversion [%] | t [h] | Product | Yield [%][a] |
| 1 (a) |  |
n.d. | 18 | 5 a | <5 |
| 2 (b) |  |
n.d. | 25 | 5 b | 29[b] |
| 3 (c) |  |
100 | 18 | 5 c | 54[b] |
| 4 (d) |  |
100 | 18 | 5 d | 54 |
| 5 (e) |  |
100 | 18 | 5 e | 80[c] |
| 6 (f) |  |
100 | 18 | 5 a | 54 |
| 7 (g) |  |
100 | 18 | 5 g | 82 |
| 8 (h) |  |
29 | 64 | 5 h | 24 |
| 9 (i) |  |
100 | 18 | 5 i | 39 |
| 10 (j) |  |
100 | 72 | 5 j | 36 |
| 11 (k) |  |
53 | 72 | 5 k | 14 |
| 12 (l) |  |
100 | 18 | 5 l | 89 |
| 13 (m) |  |
n.d. | 18 | 5 m | <5 |
[a] Isolated yields. [b] 10 equivalents of 1 used. [c] Combined yield of 7-methoxy and 9-methoxy regioisomers; 64 and 16 %, respectively.