1H-2-Benzopyran-1,4(3H)-dione → (3Z)-3-{[4-(4-chlorophenyl)cyclohexyl]methylidene}-1H-2-benzopyran-1,4(3H)-dione
反応式
[CH:1]1[CH:6]=[CH:5][C:4]2[C:7]([C:9]([OH:26])=[C:10]([C@@H:13]3[CH2:18][CH2:17][C@@H:16]([C:19]4[CH:24]=[CH:23][C:22]([Cl:25])=[CH:21][CH:20]=4)[CH2:15][CH2:14]3)[C:11](=[O:12])[C:3]=2[CH:2]=1)=[O:8].C1(=O)C2C=CC=CC=2C(=O)CO1.ClC1C=CC(C2CCC(C=O)CC2)=CC=1>>[Cl:25][C:22]1[CH:23]=[CH:24][C:19]([CH:16]2[CH2:15][CH2:14][CH:13](/[CH:10]=[C:9]3\[O:26][C:11](=[O:12])[C:3]4[CH:2]=[CH:1][CH:6]=[CH:5][C:4]=4[C:7]\3=[O:8])[CH2:18][CH2:17]2)=[CH:20][CH:21]=1参加物
4
実験手順
The present invention provides a new process for the preparation of atovaquone, which process comprises reacting 1H-2-benzopyran-1,4(3H)-dione (compound of formula (III)) with 4-(4-chlorophenyl)cyclohexanecarbaldehyde (compound of formula (IV)) to produce the novel intermediate (3Z)-3-{[4-(4-chlorophenyl)cyclohexyl]methylidene}-1H-2-benzopyran-1,4(3H)-dione (compound of formula (II)) which then undergoes internal rearrangement to produce atovaquone (compound of formula (I)).