US 12,331,021 B2
Total synthesis of pirfenidone
Lihua Zhou, Suzhou (CN)
Assigned to SUZHOU FUDE ZHAOFENG BIOCHEMICAL TECHNOLOGY CO., LTD, Suzhou (CN)
Appl. No. 17/434,820
Filed by Suzhou Fude Zhaofeng Biochemical Technology Co., Ltd, Suzhou (CN)
PCT Filed Sep. 10, 2020, PCT No. PCT/CN2020/114479
§ 371(c)(1), (2) Date Aug. 30, 2021,
PCT Pub. No. WO2022/051984, PCT Pub. Date Mar. 17, 2022.
Prior Publication US 2022/0251042 A1, Aug. 11, 2022
Int. Cl. C07D 213/64 (2006.01)
CPC C07D 213/64 (2013.01) 8 Claims
 
1. A method for manufacturing Pirfenidone of Formula (1),

OG Complex Work Unit Chemistry
which comprises the steps of:
(a) reacting 5-Methyl-3,4-dihydro-2-pyridone (4) and halobenzene (5) in the presence of a base, a copper catalyst and a ligand to form 5-methyl-1-phenyl-3,4-dihydropyridin-2(1H)-one (6),

OG Complex Work Unit Chemistry
wherein X is selected from the group consisting of —Cl, —Br, and —I,
(b) an oxidation of 5-methyl-1-phenyl-3,4-dihydropyridin-2(1H)-one (6) to Pirfenidone (1) in the presence of a copper catalyst and an oxidant

OG Complex Work Unit Chemistry
wherein the ligand of step (a) is selected from compound of formula (7), L1 and L5,

OG Complex Work Unit Chemistry
and
wherein R is selected from any alkyl and substituted/unsubstituted aryl groups.