Hydrochloric Acid → HCID 75606758, compound

Participants

Reaction Conditions

Reaction Steps

The semi-crude 5-(3,5-dimethylisoxazol-4-yl)-1-(4-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carbaldehyde was mixed with hydroxylamine hydrochloride (100 mg, 0.014 mmol) and pyridine (0.15 mL) in dry ethanol (1.5 mL) and heated at 150° C. for 10 min in the microwave. 1 M HCl and CH2Cl2 were added and the phases were separated. The oxime was purified on preparative HPLC to give E3 5-(3,5-dimethylisoxazol-4-yl)-1-(4-hydroxyphenyl)-3-methyl-1H-pyrazole-4-carbaldehyde oxime (37 mg, 50%). Identification of the title compound by 1H-NMR showed that the product was an approximately 1:1 mixture of the (E) and (Z) oxime isomers. ES/MS m/z: 313.17 (M+H), 311.19 (M−H); 1H NMR (acetone-d6, 500 MHz): 7.83 s 1H, 7.13 m 2H, 6.87 m 2H; 2.41 s 3H, 1.88 s 3H.

Provenance & Evidence