反应详情

(Trimethylsilyl)diazomethane (2.0M in hexanes, 25 ml) was added slowly with stirring under nitrogen to ethyl 6-methyl-4-oxo-2-heptynoate (7.0 g) in drytetrahydrofuran (20 ml) in a cold water bath. After 16 hours the reaction was evaporated to an oil, which was subjected to chromatography on silica (ethyl acetate/isohexane 1:2) to give the first eluted product, ethyl 5-(3-methyl-1-oxobutyl)-1H-pyrazole4-carboxylate (2.33 g).

1. customAfter 16 hours the reaction was evaporated to an oil, which