反应详情

温度

65 °C

To 28 l of 90% aqueous ethanol (water:ethanol =1:9, v/v), 7.74 kg of L-tartaric acid was added and dissolved by heating at 65° C. To the resulting solution was added 9.41 kg of (-)-(S)-2,8-dimethyl-3-methylene-1-oxa-8azaspiro[4.5]decane dropwise. The mixture was allowed to cool and maintained for crystallization at 0° C. for 15 hours. The resulting crystals were collected by filtration and dried under reduced pressure to give 14.76 kg of (-)-(S)-2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane L-tartrate monohydrate. The physicochemical properties of this compound were in agreement with those of the compound obtained in Example 1.

1. dissolutiondissolved
2. temperatureto cool
3. temperaturemaintained for crystallization at 0° C. for 15 hours
4. filtrationThe resulting crystals were collected by filtration
5. customdried under reduced pressure