反应详情

As depicted in Scheme 25 below, 2-(4-nitrophenyl)thiazole (19.9 mmol) dissolved in ether (20 ml) is added dropwise over 1 hour to a stirred and cooled (−78° C.) solution of butyl lithium (1.5 M) in n-hexane (20 ml, 29.9 mmol), diluted with ether (50 ml). The mixture is stirred at −78° C. for 30 minutes and then a solution of N-formylmorpholine (29.9 mmol) in ether (30 ml) is added dropwise over a time period of 15 minutes. After 30 minutes at −78° C., the mixture is washed with saturated aqueous NaHCO3 (30 ml) and extracted with ether (2×20 ml). The organic phase is dried over Na2SO4 and the solvent is removed under reduced pressure to give the crude 2-(4-Nitro-phenyl)-thiazole-5-carbaldehyde.

1. additionis added dropwise over 1 hour to
2. stirringThe mixture is stirred at −78° C. for 30 minutes
3. washthe mixture is washed with saturated aqueous NaHCO3 (30 ml)
4. extractionextracted with ether (2×20 ml)
5. dry with materialThe organic phase is dried over Na2SO4
6. customthe solvent is removed under reduced pressure