反应详情

温度

95 °C

A mixture of 3,5-dimethyl-1H-pyrrole-2-carbaldehyde (2.5 g, 20 mmol) in THF (40 mL), water (20 mL), acetic acid (3 mL), formaldehyde (37% wt. % solution in water, 5 mL) and the appropriate amine (30 mL) was heated to reflux (oil bath 90-100° C.) for 6 hours and then stirred at rt for overnight. The reaction was concentrated to a volume of 30 mL, basified with 2N NaOH and extracted with ethyl acetate (2×150 mL) and DCM (4×100 mL). The combined organic layers were concentrated and the residue was purified on a silica gel column to give 2.3 g (49%) of 4-(4-hydroxy-piperidin-1-ylmethyl)-3,5-dimethyl-1H-pyrrole-2-carbaldehyde as a solid.

1. concentrationThe reaction was concentrated to a volume of 30 mL
2. extractionextracted with ethyl acetate (2×150 mL) and DCM (4×100 mL)
3. concentrationThe combined organic layers were concentrated
4. customthe residue was purified on a silica gel column