[NH2:1][C:2]1[CH:3]=[N:4][CH:5]=[C:6]([Br:8])[CH:7]=1.N1C=CC=CC=1.[C:15](Cl)(=[O:19])[CH:16]([CH3:18])[CH3:17]>C(Cl)Cl>[Br:8][C:6]1[CH:7]=[C:2]([NH:1][C:15](=[O:19])[CH:16]([CH3:18])[CH3:17])[CH:3]=[N:4][CH:5]=13-Amino-5-bromo pyridine (XXX) (1 eq) was dissolved in DCM and cooled to 0° C. before adding pyridine (2.2 eq) and isobutyryl chloride (XXXI) (1.1 eq). The reaction mixture was stirred at r.t. for 15 h until TLC showed the reaction was complete. The reaction mixture was diluted with DCM and washed with water. The organic extract was dried, concentrated and purified by column chromatography using silica gel (100-200 mesh) to afford N-(5-bromopyridin-3-yl)isobutyramide (XXXII) as a off white solid, (71% yield). 1H NMR (CDCl3) δ ppm 8.55-8.35 (m, 3H), 7.32 (s, 1H), 2.59-2.48 (m, 1H), 1.28-1.27 (d, 6H); ESIMS found C9H11BrN2O m/z 243.05(M+H).
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