反应详情

1-Isobutyl-3-methyl-spiro[1,2,3,4-tetrahydroquinazoline-4,4'-imidazolidine]-2,2',5'-trione (0.76 g) as prepared in Example 37 is suspended in acetic acid (15 ml) and thereto are added sulfuryl chloride (0.3 ml) and a slight amount of iodine, and the mixture is stirred at room temperature for 19 hours. The reaction mixture is poured into ice-water, and the precipitates are taken by filtration and the crystals are dissolved in 10% aqueous sodium hydroxide. The undissolved materials are filtered off, and the filtrate is neutralized with 10% hydrochloric acid, and the precipitates are taken by filtration (this dissolution and precipitation procedure is repeated). The precipitates are taken by filteration and dried to give 6-chloro-1-isobutyl-3-methyl-spiro[1,2,3,4-tetrahydroquinazoline-4,4'-imidazolidine]-2,2',5'-trione (0.45 g).

1. filtrationthe precipitates are taken by filtration
2. dissolutionthe crystals are dissolved in 10% aqueous sodium hydroxide
3. filtrationThe undissolved materials are filtered off
4. filtrationthe precipitates are taken by filtration (
5. dissolutionthis dissolution and precipitation procedure
6. customdried