Method for reducing nitro group of candesartan cilexetil intermediate into amino group

• Main Authors: QIAO ZAIYIN, LEI YU, CHEN LIYANG, HE HAIBING, DENG PENG, GE SHAOYONG
• Format: Patent
• Language: Chinese; English
• Published: 06.03.2013
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

The invention discloses a method for reducing the nitro group of candesartan cilexetil intermediate into an amino group. The method mainly includes the following steps: (1) according to the weight ratio of 1:3 to 15:0.02 to 0.05, the candesartan cilexetil intermediate, solvent and catalyst are added into an autoclave; (2) the autoclave is closed, pressure is decreased, and nitrogen is used for replacement; (3) hydrogen is filled, the pressure of the hydrogen is controlled, and when the pressure of the hydrogen is higher than 0MPa and lower than or equal to 10MPa, an intake valve is closed; (4) reaction takes place under the condition of 20 DEG C to 70 DEG C; (5) after reaction is finished, material is discharged, post-treatment is carried out, and thereby therefore a finished product is prepared; and the catalyst is palladium/carbon catalyst or palladium hydroxide/carbon catalyst. The method mainly overcomes the defects of relatively high intermediate control requirement and relatively difficulty in operation