Hydrochloric Acid → 1-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]-3-methyl-1H-pyrazole-4-carbaldehyde

Participants

Reaction Steps

To a solution (150 mL) of methyl 1-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]-3-methyl-1H-pyrazole-4-carboxylate (7.0 g) synthesized above in tetrahydrofuran was added dropwise diisobutylaluminum hydride (1.5M toluene solution, 58.4 mL) at 0° C. After stirring for 30 min, the reaction mixture was poured into 2N hydrochloric acid of 0° C., and the mixture was extracted with ethyl acetate. The extract was dried over magnesium sulfate, and the solvent was evaporated. The residue was treated in the same manner as in Example 1(5) to give the title object compound (1.7 g, 27%) as a pale-yellow solid.

Provenance & Evidence