反应详情

To 710 mg (2.3 mmole) of 3-chloro-4,5-dihydro-α-phthalimido-5-isoxazole acetic acid in 15 ml of water is added 260 μl of hydrazine hydrate and the solution stirred at 50° for 7 hours. After cooling, the solution is adjusted to pH 5.5 with acetic acid (80 μl), filtered, and the precipitate washed with 13 ml water. The filtrate is diluted with 200 ml of 2-butanol and allowed to crystallized in the refrigerator for 18 hours. Filtration yielded 240 mg of (αS,5S)-α-amino-3-chloro-4,5-dihydro-5-isoxazole acetic acid; concentrating the mother liquors approximately 15% afforded 50 mg of a second crop of (αS,5S)-α-amino-3-chloro-4,5-dihydro-5-isoxazole acetic acid (71%).

1. temperatureAfter cooling
2. filtrationfiltered
3. washthe precipitate washed with 13 ml water
4. additionThe filtrate is diluted with 200 ml of 2-butanol
5. customto crystallized in the refrigerator for 18 hours
6. filtrationFiltration