Cl.[NH2:2][CH2:3][C:4]([O:6][CH2:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)=[O:5].[Cl:14][C:15]1[CH:20]=[C:19]([C:21](=O)[CH2:22][CH2:23][C:24](=O)[CH3:25])[CH:18]=[CH:17][N:16]=1.C(=O)(O)[O-].[Na+]>ClCCl>[Cl:14][C:15]1[CH:20]=[C:19]([C:21]2[N:2]([CH2:3][C:4]([O:6][CH2:7][C:8]3[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=3)=[O:5])[C:24]([CH3:25])=[CH:23][CH:22]=2)[CH:18]=[CH:17][N:16]=1A slurry of benzyl 2-aminoacetate hydrochloride (922 mg, 4.57 mmol), 1-(2-chloropyridin-4-yl)pentane-1,4-dione (968 mg, 4.57 mmol), and solid sodium bicarbonate (961 mg, 11.4 mmol) in dichloromethane (15.2 mL) was heated to 45° C. for 14 hours. A significant amount of starting material was observed after 14 hours by LC/MS, so the reaction was heated to 65° C. The reaction was allowed to stir (with occasional monitoring by LCMS) at this temperature for 11 days. The reaction was then allowed to cool down to room temperature and poured onto water and extracted with dichloromethane (3×50 mL), dried (sodium sulfate), filtered, and concentrated to a dark orange residue. Purification was achieved by column chromatography (Luknova 80 g, 20 mL/min) using 5 to 45% ethyl acetate in hexanes over 60 minutes. The product, benzyl 2-(2-(2-chloropyridin-4-yl)-5-methyl-1H-pyrrol-1-yl)acetate was isolated as a light orange oil (890 mg, 2.61 mmol, 57% yield). 1H NMR (400 MHz, CDCl3): δ (ppm) 8.23 (d, 1H), 7.36-7.40 (m, 5H), 7.21 (m, 1H), 7.02 (dd, 1H), 6.37 (d, 1H), 6.07 (d, 1H), 5.25 (s, 2H), 4.64 (s, 2H), 2.22 (s, 3H).
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