Phosphorus oxychloride → 3-Chloro-7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-phthalide
Reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[C:7]([O:9][CH3:10])[N:6]=[C:5]([O:11][C:12]2[CH:13]=[CH:14][CH:15]=[C:16]3[C:21]=2[C:19](=[O:20])[O:18][CH:17]3O)[N:4]=1.P(Cl)(Cl)([Cl:25])=O>O>[Cl:25][CH:17]1[C:16]2[C:21](=[C:12]([O:11][C:5]3[N:4]=[C:3]([O:2][CH3:1])[CH:8]=[C:7]([O:9][CH3:10])[N:6]=3)[CH:13]=[CH:14][CH:15]=2)[C:19](=[O:20])[O:18]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 90 °C
Procedure
2.3 g of 7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-3-hydroxy-phthalide (see Example 84) are suspended in approximately 40 ml of phosphorus oxychloride, and the suspension is heated at 90° C. for 2 hours. The reaction mixture is then introduced at from 35° to 45° C. into 250 ml of water. It is then diluted with a further 500 ml of water and the crystals which separate are filtered off and washed neutral with water to yield pure 3-chloro-7-[(4,6-dimethoxy-pyrimidin-2-yl)oxy]-phthalide in the form of slightly yellowish crystals, m.p. 143°-144° C.