Ammonia → 3,4-Dimethoxy-6-nitrobenzamide

HRID 992361Notes

Reaction equation

HRID 992361 reaction equation
[CH3:1][O:2][C:3]1[C:11]([O:12][CH3:13])=[CH:10][C:6]([C:7](O)=[O:8])=[C:5]([N+:14]([O-:16])=[O:15])[CH:4]=1.S(Cl)(Cl)=O.[NH3:21]>>[CH3:1][O:2][C:3]1[C:11]([O:12][CH3:13])=[CH:10][C:6]([C:7]([NH2:21])=[O:8])=[C:5]([N+:14]([O-:16])=[O:15])[CH:4]=1

Participants

4

Procedure

4,5-Dimethoxy-2-nitrobenzoic acid (1) was treated with thionyl chloride and then reacted with ammonia to give 4,5-dimethoxy-2-nitrobenzamide (2) as described by F. Nomoto et al. Chem. Pharm. Bull. 1990, 38, 1591-1595. The nitro group in compound (2) was reduced with sodium borohydride in the presence of copper sulfate (see C. L. Thomas Catalytic Processes and Proven Catalysts Academic Press, New York (1970)) to give 4,5-dimethoxy-2-aminobenzamide (3) which was cyclized by refluxing with formic acid to give 6,7-dimethoxyquinazoline-4(3H)-one (4). Compound (4) was refluxed with phosphorus oxytrichloride to provide compound (5), which is a useful intermediate for preparing compounds of formula I wherein X is NH. Reaction of compound (5) with the requiste aniline provided the following compounds of formula I:

Sources & evidence

ORD record
ord-587691d4a163446ba16a7bf1a63ff68a
Source dataset
uspto-grants-2002_10
Patent number
US06469013B2

Reaction notes

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