[N:1]1[CH:6]=[CH:5][CH:4]=[C:3]([CH2:7][CH2:8][CH2:9][NH:10]C(=O)OC(C)(C)C)[CH:2]=1.C(O)(C(F)(F)F)=O>C(Cl)Cl>[N:1]1[CH:6]=[CH:5][CH:4]=[C:3]([CH2:7][CH2:8][CH2:9][NH2:10])[CH:2]=1(See FIG. 10.) To a solution of 29 (249 mg, 1.05 mmol) in CH2Cl2 (3 mL) at 0° C. was added TFA (2 mL, excess), the ice bath was removed and the resultant solution was stirred at ambient temperature for 1 h. The solvent and excess TFA were removed with a stream of nitrogen and the residue was partitioned between HCl(aq) (1.0 M, 2 mL) and EtOAc (10 mL). The aqueous fraction was collected and subsequently washed with EtOAc (2×10 mL). To the remaining aqueous fraction was added CH2Cl2 (20 mL) and water (20 mL) and the pH was adjusted to 10 with NaOH(aq) (10 N) while stirring. The organic fraction was collected and the remaining aqueous fraction was extracted with CH2Cl2 (2×15 mL). The combined organic fractions were dried (Na2SO4), filtered and the solvent was removed in vacuo to afford the title compound 30 (97 mg, 68% yield) as a yellow oil: 1H NMR (CDCl3) δ 8.35 (m, 2H), 7.42 (m, 1H), 7.12 (m, 1H), 2.67-2.54 (m, 4H), 1.73-1.63 (m, 4H); LRMS (ESI) m/z calcd for C8H13N2 [M+H]+ 137. found 137.
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