反应详情

温度

-72 °C

Under argon 12.3 g (41.7 mmol) of dimethyl 1-(3-chloropyridin-2-yl)-1H-pyrazole-3,5-dicarboxylate are introduced in 430 ml of tetrahydrofuran and this initial charge is cooled to −72° C. and admixed dropwise with 100 ml (100 mmol of a 1 M solution in hexane) of diisobutylaluminium hydride. The mixture is allowed to warm to 0° C. overnight and 65 ml of water are cautiously added. The solvents are removed on a rotary evaporator and the residue is extracted to exhaustion with methanol on a Soxhlet apparatus. Following removal of the solvent, the residue is purified on silica gel (cyclohexane/ethyl acetate=2:1→1:1).

1. additionthis initial charge
2. temperatureto warm to 0° C. overnight
3. customThe solvents are removed on a rotary evaporator
4. extractionthe residue is extracted to exhaustion with methanol on a Soxhlet apparatus
5. customremoval of the solvent
6. customthe residue is purified on silica gel (cyclohexane/ethyl acetate=2:1→1:1)