C1C(=O)N([Br:8])C(=O)C1.[Cl:9][C:10]1[N:19]=[CH:18][C:17]2[C:12](=[C:13]([OH:20])[CH:14]=[CH:15][CH:16]=2)[N:11]=1>CN1C(=O)CCC1.C(OCC)(=O)C>[Br:8][C:16]1[CH:15]=[CH:14][C:13]([OH:20])=[C:12]2[C:17]=1[CH:18]=[N:19][C:10]([Cl:9])=[N:11]2Solid NBS (1 eq) was added to a stirred solution of 2-chloroquinazolin-8-ol (1 eq) (See example 1 for synthesis) in NMP at 0° C. under argon. After stirring at 0° C. for 30 min, LCMS showed that the reaction was complete. The formation of both 5-bromo (Major) and 7-bromo (Minor) isomers along with 5,7 dibromo product was observed. The reaction mixture was diluted with ethyl acetate and washed with satd. sodium bicarbonate, water and brine. Dried, filtered and concentrated. The crude was purified by flash chromatography (3-5% EtOAc/Hexane) to provide 5-bromo-2-chloroquinazolin-8-ol as a white solid in 60% yield. ES/MS m/z 259.2 (MH+).
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