反应详情

A solution of 994 mg of ethyl 3-t-butyldimethylsilyloxy-3-(2-chloropyridin-3-yl)-2-methylaminopropionate (prepared as described in Preparation 79) and 393 mg of 1,5-diazabicyclo[4.3.0]non-5-ene in 5 ml of dimethylformamide was stirred at 150° C. for 5 hours. At the end of this time, the reaction mixture was poured into a saturated aqueous solution of ammonium chloride, after which it was extracted with ethyl acetate. The extract was washed with an aqueous solution of sodium chloride and dried over anhydrous sodium sulfate, after which the solvent was removed by distillation under reduced pressure. The residue was purified by column chromatography through silica gel, using a gradient elution method, with mixtures of hexane and ethyl acetate in ratios ranging from 9:1 to 5:1 by volume as the eluent, to give 150 mg of the title compound having Rf=0.40 (on silica gel thin layer chromatography using a 3:1 by volume mixture of hexane and ethyl acetate as the developing solvent).

1. extractionafter which it was extracted with ethyl acetate
2. washThe extract was washed with an aqueous solution of sodium chloride
3. dry with materialdried over anhydrous sodium sulfate
4. customafter which the solvent was removed by distillation under reduced pressure
5. customThe residue was purified by column chromatography through silica gel
6. washa gradient elution method