Potassium Carbonate → Dimethyl 1-[2-(2-methoxyethoxy)ethyl]-4-nitro-1H-pyrazole-3,5-dicarboxylate

Temperature

30 °C

Dimethyl 4-nitro-1H-pyrazole-3,5-dicarboxylate (9.53 g, 41.6 mmol) and potassium carbonate (3.44 g, 25 mmol) were dissolved in N,N-dimethylformamide (140 mL) under nitrogen. The mixture was then treated with a solution of 1-bromo-2-(2-methoxyethoxy)ethane (9.90 g, 54 mmol) in N,N-dimethylformamide (10 mL). The reaction mixture was stirred at 30° C. for 18 hours and then allowed to cool to room temperature. Additional 1-bromo-2-(2-methoxyethoxy)ethane (9.90 g, 54 mmol) and potassium carbonate (3.44 g, 25 mmol) were added and the reaction mixture allowed to stir at 30° C. for 4 hours. The reaction mixture was concentrated in vacuo and the residue taken up in ethyl acetate (200 mL) and water (200 mL). The aqueous was separated and washed with ethyl acetate (200 mL), the organics were combined and washed with water. The organic layer was dried over magnesium sulphate and concentrated in vacuo to yield the title product. 1H NMR (CDCl3, 400 MHz) δ: 3.25 (s, 3H), 3.38 (m, 2H), 3.50 (m, 2H), 3.80 (t, 2H), 3.92 (s, 3H), 3.93 (s, 3H), 4.77 (t, 2H). MS APCI+ m/z 333 [MH]+

1. temperatureto cool to room temperature
2. stirringto stir at 30° C. for 4 hours
3. concentrationThe reaction mixture was concentrated in vacuo
4. customThe aqueous was separated
5. washwashed with ethyl acetate (200 mL)
6. washwashed with water
7. dry with materialThe organic layer was dried over magnesium sulphate
8. concentrationconcentrated in vacuo

ORD record

ord-ea07b9c3204d4a81b127fbbf3a188ec6

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08097621B2