反应详情

To 143 mg of 8-ethoxy-4-hydroxy-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-2-one in 1 ml of tetrahydrofuran were added 36 μl of pyridine and 53 μl of pivaloyl chloride. After stirring at room temperature for 20 hours, water and ethyl acetate were added and the phases separated. The aqueous phase was extracted with ethyl acetate, the combined organic phases dried with sodium sulfate, filtered and concentrated. Chromatography (heptane/ethyl acetate 2:1) yielded 117 mg of 2,2-dimethyl-propionic acid 8-ethoxy-2-oxo-3-(2,4,6-trimethyl-phenyl)-1,8-diaza-spiro[4.5]dec-3-en-4-yl ester (title compound A54) as a solid, mp: 230-231° C.

1. customthe phases separated
2. extractionThe aqueous phase was extracted with ethyl acetate
3. dry with materialthe combined organic phases dried with sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated