反应详情

A mixture of 8-(2,6-difluoro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid ethyl ester (885 mg, 2.37 mmol) (Step 185.2), a 2N aqueous solution of LiOH (8 mL) and THF (8 mL) was stirred for 16 h at rt. THF was removed under vacuum. The resulting mixture was diluted with Et2O/H2O. The aqueous layer was separated and extracted with Et2O. The aqueous layer was acidified to pH 6 by addition of a 2N aqueous solution of HCl. The resulting yellow precipitate was collected by vacuum filtration and dried to provide 701 mg of the title compound: ESI-MS: 347 [M+H]+; tR=3.16 min (System 1)

1. customTHF was removed under vacuum
2. additionThe resulting mixture was diluted with Et2O/H2O
3. customThe aqueous layer was separated
4. extractionextracted with Et2O
5. additionThe aqueous layer was acidified to pH 6 by addition of a 2N aqueous solution of HCl
6. filtrationThe resulting yellow precipitate was collected by vacuum filtration
7. customdried