反应详情

To a solution of (Z)-2-(2-aminothiazol-4-yl)-2-(((1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl)oxy)imino)acetic acid (120 g, 364 mmol) in Dichloromethane (DCM) (840 mL) in an ice bath was added TEA (76 mL, 546 mmol), a solution of Boc-anhydride (110 mL, 474 mmol), and DMAP (8.90 g, 72.9 mmol). The mixture was stirred at r.t. over night. The solvent was then removed under vacuum. Water (1 L) and diisopropylether (700 mL) were added to the mixture. The aqueous layer was separated, washed with toluene and was adjusted to pH ˜2 with 2N HCl. The aqueous layer was extracted with toluene. The organic layer was concentrated. IPE was added and the insoluble material was tritulated. The material was collected by filtration and dried to afford (Z)-2-(((1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl)oxy)imino)-2-(2-((tert-butoxycarbonyl)amino)thiazol-4-yl)acetic acid (69 g, 145 mmol, 39.7% yield) as a white powder. LCMS: (M+H)+: 430.0

1. customThe solvent was then removed under vacuum
2. additionWater (1 L) and diisopropylether (700 mL) were added to the mixture
3. customThe aqueous layer was separated
4. washwashed with toluene
5. extractionThe aqueous layer was extracted with toluene
6. concentrationThe organic layer was concentrated
7. additionIPE was added
8. filtrationThe material was collected by filtration
9. customdried