反应详情

To a solution of tert-butyl 5-cyano-3-methylpicolinate (4.18 g, 19.15 mmol) in DCM (96 ml) was added TFA (148 ml, 1915 mmol), and the brown solution was stirred at RT for 2 h. The reaction mixture was concentrated. To the brown red residue was added EtOAc and it changed into a yellow slurry. It was concentrated again and dried on high vacuum. The reaction was triturated with 30 mL of MTBE and 50 ml of hexanes to yield 5-cyano-3-methylpicolinic acid (2.91 g, 17.95 mmol, 94% yield) as yellow solid. MS m/z=163.2 (M+H).

1. concentrationThe reaction mixture was concentrated
2. additionTo the brown red residue was added EtOAc and it
3. concentrationIt was concentrated again
4. customdried on high vacuum
5. customThe reaction was triturated with 30 mL of MTBE and 50 ml of hexanes