反应详情

温度

200 °C

Ethyl 4-fluorobenzoate (0.151 mL, 1 mmol), 2,2-dimethylpiperazine (0.137 g, 1.20 mmol) and N-ethyl-N-propan-2-ylpropan-2-amine (0.349 mL, 2.00 mmol) were dissolved in DMA (2 mL) and sealed into a microwave tube. The reaction was heated to 200° C. for 4 h in the microwave reactor and cooled to room temperature. The crude mixture was purified by ion exchange chromatography, using an SCX column. The desired product was eluted from the column using 3.5M ammonia in methanol, fractions were evaporated to dryness to afford an oil. The crude product was purified by silica column chromatography, eluting with a gradient of 0 to 10% 2M ammonia/MeOH in DCM. Pure fractions were evaporated to dryness to afford ethyl 4-(3,3-dimethylpiperazin-1-yl)benzoate (0.145 g, 55.3%) as a white solid. 1H NMR (399.9 MHz, CDCl3) δ 1.15 (6H, d), 1.37 (3H, t), 2.38 (1H, d), 2.41 (1H, d), 2.96-3.04 (2H, m), 3.65-3.69 (2H, m), 4.33 (2H, q), 6.84-6.87 (2H, m), 7.89-7.93 (2H, m). MS: m/z 266 (MH+).

1. customsealed into a microwave tube
2. temperaturecooled to room temperature
3. customThe crude mixture was purified by ion exchange chromatography
4. washThe desired product was eluted from the column
5. customwere evaporated to dryness
6. customto afford an oil
7. customThe crude product was purified by silica column chromatography
8. washeluting with a gradient of 0 to 10% 2M ammonia/MeOH in DCM
9. customPure fractions were evaporated to dryness