Ammonia → 3,4-Dimethoxy-6-nitrobenzamide

HRID 2298871Notes

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

Reactant 3

HCID 222Ammonia

HCID 24386Thionyl Chloride

HCID 786904,5-Dimethoxy-2-nitrobenzoic acid

Product 1

HCID 27361933,4-Dimethoxy-6-nitrobenzamide

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-f93341c6e14d495bba834a7e6b62560b
Source dataset: uspto-grants-2002_12
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06495556B2

Reaction notes

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