反应详情

At room temperature, to a mixture of 3-(4-methoxy-3-methyl-phenyl)-3-oxo-propionic acid ethyl ester (described in Reference Preparation example 89) 14.8 g and toluene 100 ml was added N-methyl hydrazine 29 g, and the resulting mixture was stirred for twelve hours. The toluene was distilled off. At room temperature, to the reaction mixture was added water 100 ml and the resulting mixture was acidified with 10% aqueous hydrochloric acid solution and was stirred for three hours. The precipitates were filtered and were washed with water 400 ml and ethyl acetate 500 ml, and then were dried under reduced pressure to give 5-hydroxy-3-(4-methoxy-3-methyl-phenyl)-1-methyl-1H-pyrazole 9.3 g.

1. distillationThe toluene was distilled off
2. additionAt room temperature, to the reaction mixture was added water 100 ml
3. stirringwas stirred for three hours
4. filtrationThe precipitates were filtered
5. washwere washed with water 400 ml and ethyl acetate 500 ml
6. customwere dried under reduced pressure