Table 1.
Characteristics of compounds 4a–p, 5–8, and 10a–g.
| Compound | R1 | R2 | R3 | X | Rx Time (h) | Yield (%) | m.p. (°C) | m.p. lit (°C) |
|---|---|---|---|---|---|---|---|---|
| 4a | 2-OH | - | - | - | 96 | 92 | 233.5–236.5 | 235–238 [53] |
| 4b | 3-OH | - | - | - | 60 | 84 | 285.5–287.0 | 285–286 [53] |
| 4c | 4-OH | - | - | - | 120 | 73 | 271.0–272.0 | 282–284 [53] |
| 4d | 2-OH | 4-Me | - | - | 24 | 60 | 221.0–223.5 | - |
| 4e | 2-OH | 5-Me | - | - | 96 | 89 | 191.5–194.5 | - |
| 4f | 2-OH | 6-Me | - | - | 168 | 88 | 264.0–267.0 | - |
| 4g | 2-OH | 4-Cl | - | - | 96 | 59 | 230.0–234.0 | - |
| 4h | 2-OH | 5-Cl | - | - | 48 | 63 | 219.5–221.5 | - |
| 4i | 2-OH | 5-COOMe | - | - | 72 | 57 | 281.0–282.0 | - |
| 4j | 3-OH | 4-OMe | - | - | 120 | 94 | 232.5–236.5 | - |
| 4k | 2-OMe | - | - | - | 168 | 94 | 211.0–214.0 | 216–217 [53] |
| 4l | 3-OMe | - | - | - | 72 | 98 | 221.0–223.0 | 221–223 [35] |
| 4m | 4-OMe | - | - | - | 48 | 94 | 285.5–287.5 | 290–292 [53] |
| 4n | 2-OMe | 4-Ome | - | - | 168 | 99 | 211.0–213.5 | - |
| 4o | 3-OMe | 4-OMe | - | - | 96 | 72 | 231.5–234.5 | 235 [53] |
| 4p | 3-OMe | 4-OMe | 5-OMe | - | 96 | 76 | 193.0–195.0 | - |
| 5 | - | - | - | - | 120 | 85 | 149.0–152.0 | - |
| 6 | - | - | - | - | 120 | 100 | 296.5 dec. | - |
| 7 | - | - | - | - | 96 | 36 | 178.0–181.0 | - |
| 8 | - | - | - | - | 240 | 97 | >300 | - |
| 10a | 2-OH | - | - | CH | 20 | 40 | 195.5–197.5 | 194–196 [54] |
| 10b | 6-OH | - | - | N | 2 | 65 | 229.0 dec. | 199–201 [55] a |
| 10c | 2-OMe | - | - | CH | 24 | 71 | 189.0–191.5 | 172–174 [63] |
| 10d | 3-OMe | - | - | CH | 2 | 65 | 166.0–168.0 | 165.5–167.5 [35] |
| 10e | 4-OMe | - | - | CH | 20 | 70 | 180.0–181.0 | 180.5–181.5 [35] |
| 10f | 2-OMe | 4-Ome | - | CH | 6 | 65 | 240.5–242.5 | - |
| 10g | 3-OMe | 4-Ome | - | CH | 48 | 68 | 159.0–161.0 | - |
a Phase transfer was observed at 199 °C.