反应详情

The following Example 14 illustrates an alternative preparation of ethyl 3-bromo-1-(3-chloro-2-pyridinyl)-4,5-dihydro-1H-pyrazole-5-carboxylate, which can be used to prepare, for example, ethyl 3-bromo-1-(3-chloro-2-pyridinyl)-1H-pyrazole-5-carboxylate (i.e. product of Example 13, Step B).