Cl[C:2]1[CH:3]=[CH:4][N:5]=[C:6]2[C:11]=1[N:10]=[CH:9][C:8]([NH2:12])=[CH:7]2.ClC1C=CN=C2C=1N=CC(N=C(C1C=CC=CC=1)C1C=CC=CC=1)=C2.Cl.C(=O)(O)[O-:40].[Na+]>O1CCCC1>[NH2:12][C:8]1[CH:7]=[C:6]2[C:11]([C:2]([OH:40])=[CH:3][CH:4]=[N:5]2)=[N:10][CH:9]=18-chloro-1,5-naphthyridin-3-amine. A round bottom flask under nitrogen was charged with 8-chloro-N-(diphenylmethylene)-1,5-naphthyridin-3-amine (315 mg, 0.92 mmol), 2M aqueous HCl (1.42 mL, 2.84 mmol), and tetrahydrofuran (0.25M, 3.67 mL). This was stirred at RT for 30 minutes. Reaction basified with aq. sodium bicarbonate solution and product extracted with dichloromethane. This was dried over sodium sulfate and concentrated to afford orange solid; which was purified via ISCO silica gel chromatography, 40 g column, 30% (90/10/1 DCM:MeOH:NH4OH)/DCM over 40 minutes to afford 7-amino-1,5-naphthyridin-4-ol (140 mg, 95% yield) as yellow solid. MS[M+H]=180.2. Calc'd for C8H6ClN3=179.6. 2) 8-chloro-N-(2-methoxyethyl)-1,5-naphthyridin-3-amine. A round bottom flask under nitrogen atmosphere was charged with 8-chloro-1,5-naphthyridin-3-amine (160 mg, 0.89 mmol), DMF (2.2 mL, 0.89 mmol). This was cooled to 0° C. and SODIUM HYDRIDE (60% dispersion in oil) (107 mg, 4.45 mmol) added portionwise. This was quickly followed by addition of 1-bromo-2-methoxyethane (0.12 mL, 1.25 mmol) dropwise via syringe. Ice bath removed and reaction mixture heated to 85° C. and stirred at this temperature for 16 hours. Reaction diluted with 5 mL of 5% MeOH/Dichloromethane, loaded onto silica gel column and eluted with 2% MeOH/DCM to afford 8-chloro-N-(2-methoxyethyl)-1,5-naphthyridin-3-amine (70 mg, 33% yield) as a light yellow solid. MS[M+H]=238.2. Calc'd for C11H12ClN3O=237.7.
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