反应详情

To a stirred solution of 3-tert-butoxy-3-oxopropanoic acid (680 mg, 4.25 mmol) and 2M dimethylamine in THF (3.18 mL, 6.37 mmol) in DMF (10 mL) was added diisopropyl-ethylamine (2.224 mL, 12.74 mmol), 4-(dimethylamino)pyridine (DMAP) (104 mg, 0.849 mmol) and O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (HATU) (2421 mg, 6.37 mmol) and the resulting mixture was stirred at room temperature for 16 h. Water was then added and the resulting mixture was extracted with ethyl acetate (2×50 mL), washed with 1N HCl (20 mL), dried (Na2SO4), filtered and concentrated to give crude product which was dissolved in CH2Cl2 (5.00 mL), treated with trifluoroacetic acid (4.91 mL, 63.7 mmol) and stirred at room temperature for 16 h. The solvent was then removed under reduced pressure to afford the title compound (230 mg, 41% yield) as a light-yellow solid, which was used in the next step without further purification. 1H NMR (500 MHz, DMSO-d6) δ: 12.1 (1 H, br s), 3.4 (2 H, s), 2.9 (3 H, s), 2.8 (3 H, s). LCMS (M+H)=132.33.

1. extractionthe resulting mixture was extracted with ethyl acetate (2×50 mL)
2. washwashed with 1N HCl (20 mL)
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customto give crude product which
7. stirringstirred at room temperature for 16 h
8. customThe solvent was then removed under reduced pressure