Paliperidone Tetradehydro Impurity → Paliperidone

Reaction equation

[F:1][C:2]1[CH:31]=[CH:30][C:5]2[C:6]([CH:9]3[CH2:14][CH2:13][N:12]([CH2:15][CH2:16][C:17]4[C:22](=[O:23])[N:21]5[CH:24]=[CH:25][CH:26]=[C:27]([OH:28])[C:20]5=[N:19][C:18]=4[CH3:29])[CH2:11][CH2:10]3)=[N:7][O:8][C:4]=2[CH:3]=1.[H][H]>[C].[Pd].C(O)(=O)C>[CH3:29][C:18]1[N:19]=[C:20]2[N:21]([CH2:24][CH2:25][CH2:26][CH:27]2[OH:28])[C:22](=[O:23])[C:17]=1[CH2:16][CH2:15][N:12]1[CH2:13][CH2:14][CH:9]([C:6]2[C:5]3[CH:30]=[CH:31][C:2]([F:1])=[CH:3][C:4]=3[O:8][N:7]=2)[CH2:10][CH2:11]1

Participants

Procedure

A mixture of 3-[2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)piperidin-1-yl]ethyl]-9-hydroxy-2-methyl-4H-pyrido-[1,2-a]pyrimidin-4-one (formula-11) (5 grams), acetic acid (25 ml) and palladium carbon (4 grams) was taken in an autoclave. Hydrogen gas with a pressure of 3.0 Kg/cm2 was applied to the above mixture at 32° C. for 9 hrs. The reaction mixture was filtered through a hyflow bed. The filtrate was treated with water (100 ml) and the pH of the filtrate was adjusted to 10 using aqueous sodium hydroxide solution. The solid formed was filtered, washed with water and dried at 50° C. to yield the title compound.