反应详情

To a solution of tert-butyl 4-({[5-bromo-2-(methoxycarbonyl)thiophen-3-yl]carbamoyl}amino)piperidine-1-carboxylate (37.6 g; compound B54a) in dry MeOH (205 ml) under argon atmosphere is added sodium methoxide (6.16 g) at RT. The reaction mixture is refluxed for 3 h, allowed to cool to RT and then poured into a solution of citric acid (21.9 g) in ice cold water (961 ml). The precipitated solid is filtered off, washed with ice cold water and dried in vacuo. The residue is taken up in MeOH (205 ml) and the resulting suspension is refluxed for 1 h. After cooling to RT all solids are filtered off, washed with MeOH and dried in vacuo to afford the title compound as a solid.

1. temperatureThe reaction mixture is refluxed for 3 h
2. filtrationThe precipitated solid is filtered off
3. washwashed with ice cold water
4. customdried in vacuo
5. temperaturethe resulting suspension is refluxed for 1 h
6. temperatureAfter cooling to RT all solids
7. filtrationare filtered off
8. washwashed with MeOH
9. customdried in vacuo