1,4-Dioxane → 3-Amino-5-bromo-1-methyl-1,2-dihydropyridin-2-one
Reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([N:10]=C(C2C=CC=CC=2)C2C=CC=CC=2)[C:5](=[O:9])[N:6]([CH3:8])[CH:7]=1.O1CCOCC1>C(OCC)(=O)C>[NH2:10][C:4]1[C:5](=[O:9])[N:6]([CH3:8])[CH:7]=[C:2]([Br:1])[CH:3]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 5-bromo-3-(diphenylmethyleneamino)-1-methylpyridin-2(1H)-one (3.82 g, 10.4 mmol) in ethyl acetate (10 mL) was added 4 MHCl/dioxane (7.8 mL, 31.3 mmol). The reaction mixture was stirred for 0.5 h and concentrated under reduced pressure. The residue was washed with tert-butyl methyl ether and filtered. The solid was dissolved in ethyl acetate (10 mL) and water (10 mL). The pH of the resulting mixture was adjusted to between 7 and 8 by adding K2CO3 gradually. The water phase was separated and extracted with dichloromethane for three times. The combined organic layer was concentrated under reduced pressure to afford 325a as a yellow solid (1.1 g, 52%). MS-ESI: [M+H]+ 202.9.