反应详情

The residue from step 1 was dissolved in HMPA (50 mL) and 8N KOH (65 mL) was added. The mixture was warmed to 120°-125° C. and stirred vigourously for 16 h. The mixture was cooled to r.t., the aqueous layer was separated, diluted with H2O (500 mL) and acidified to pH 6 with 6N HCl under vigourous stirring. After cooling in an ice bath, the solid was collected and air dried. It was dissolved in warm IN NaOH and washed once with ETOAc. The aqueous layer was acidified to pH 6 with 6N HCl and cooled again in an ice bath. The solid was filtered and air dried to yield the title compound (4.4 g, 40 %).

1. temperatureThe mixture was warmed to 120°-125° C.
2. customthe aqueous layer was separated
3. additiondiluted with H2O (500 mL)
4. temperatureAfter cooling in an ice bath
5. customthe solid was collected
6. customair dried
7. dissolutionIt was dissolved
8. temperaturein warm IN NaOH
9. washwashed once with ETOAc
10. temperaturecooled again in an ice bath
11. filtrationThe solid was filtered
12. customair dried