反应详情

To a solution of tert-butyl 4-(4-ethylpiperazin-1-yl)-2-nitrophenylcarbamate (3.3 g, 9.43 mmol) in DCM (50 mL) was added TFA (20 mL) at 0° C., the resulting mixture was stirred for 3 hours at rt. After removal of all volatiles in vacuo, the residue was re-dissolved in DCM, neutralized with saturated aqueous K2CO3 and extracted with DCM. The combined extracts were concentrated to obtain the title compound (2.1 g, yield: 90%), which was used directly in the next step. 1H NMR (400 MHz, DMSO-d6) δ 1.02 (t, 3H), 2.36 (q, 2H), 2.47-2.49 (m, 4H) 2.97-3.00 (m, 4H), 6.97 (d, 1H), 7.20 (s, 2H), 7.25 (s, 1H), 7.34 (dd, 1H); MS (ESI): 251 [M+H]+.

1. customAfter removal of all volatiles in vacuo
2. dissolutionthe residue was re-dissolved in DCM
3. extractionextracted with DCM
4. concentrationThe combined extracts were concentrated