反应详情

The solution of (4-methyl-pyridin-2-yl)-carbamic acid tert-butyl ester (100 mg, 0.48 mmol) in dry THF (5 mL) is cooled down to −78° C. The 1.6 M n-BuLi in hexane solution (1.5 mL, 2.4 mmol) is added dropwise at −78° C. Then the cooling bath is removed and the mixture is stirred at room temperature for 15 min. The reaction mixture is cooled down to −78° C. again and 1-phenyl-ethanone (0.28 mL, 2.4 mmol) is added. The mixture is stirred for another 30 min at −78° C. and saturated NH4Cl aquaous solution (25 mL) is added. The reaction mixture is then warmed up to room temperature and EtOAc (50 mL) is added along with water (30 mL). The resulting mixture is stirred for 10 min and the aqueous layer is separated and extracted with EtOAc (2×35 ml). The organic layers are combined and concentrated to give the crude product. Purification by silica flash column chromatography using MeOH in DCM (gradient from 0% to 10%) afforded 140 mg of desired product.

1. customThen the cooling bath is removed
2. temperatureThe reaction mixture is cooled down to −78° C. again
3. stirringThe mixture is stirred for another 30 min at −78° C.
4. temperatureThe reaction mixture is then warmed up to room temperature
5. stirringThe resulting mixture is stirred for 10 min
6. customthe aqueous layer is separated
7. extractionextracted with EtOAc (2×35 ml)
8. concentrationconcentrated
9. customto give the crude product
10. customPurification by silica flash column chromatography