反应详情

A mixture of 4-[4-bromo-5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-2-methyl-benzoic acid ethyl ester (0.71 g, 1.35 mmol) (Example 1.6), lithium hydroxide monohydrate (0.17 g, 4 mmol), methanol (25 ml) and water (5 ml) was stirred at ambient temperature for 60 hours. The mixture was concentrated and the residue dissolved in water. The solution was acidified by addition of aqueous hydrochloric acid (1N). The precipitate was isolated by filtration and dried under vacuum to afford 4-[4-bromo-5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydroisoxazol-3-yl]-2-methyl-benzoic acid (0.59 g, 88% yield) as a white powder. 1H-NMR (CDCl3, 400 MHz): 8.05-7.45 (m, 6H), 5.87 (s, 1H), 2.65 (s, 3H) ppm.

1. concentrationThe mixture was concentrated
2. dissolutionthe residue dissolved in water
3. additionThe solution was acidified by addition of aqueous hydrochloric acid (1N)
4. customThe precipitate was isolated by filtration
5. customdried under vacuum