The acylation of 3-aminobenzoic acid with acetic anhydride in ethyl acetate gives the corresponding acetamide (II), which is treated with SOCl2 in refluxing ethyl acetate yielding 3-(trifluoroacetamido)benzoyl chloride (III). The reaction of (III) with urea (IV) in toluene at 100 C gives the acylated urea (V), which is deprotected with butylamine in refluxing methanol to afford N-(3-aminobenzoyl)urea (VI). The acylation of (VI) with chloroacetyl chloride (VII) in dimethylacetamide provides the corresponding amide (VIII), which is finally treated with NaI in dimethylacetamide.
3-Aminobenzoic acid (I) was protected as the trifluoroacetamide (II) using trifluoroacetic anhydride and then converted to acid chloride (III) by means of SOCl2. Subsequent condensation of (III) with urea provided 3-(trifluoroacetamido)benzoylurea (IV). After cleavage of the trifluoroacetamido group of (IV) by treatment with methanolic n-butylamine, the deprotected aniline (V) was coupled with bromoacetyl bromide in DMA to furnish the title bromoacetamide.