Potassium Phosphate, Tribasic → 2-(3-(tert-butylamino)-6-fluoro-2-methylquinoxalin-5-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one

Participants

Reaction Conditions

Reaction Steps

A glass microwave reaction vessel (80 mL) was charged with 8-bromo-N-(tert-butyl)-7-fluoro-3-methylquinoxalin-2-amine (286a) (1.20 g, 3.84 mmol) and 2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (609; 1.81 g, 6.92 mmol) in 1,4-dioxane (15 mL)/water (4.8 mL). Then Pd2(dba)3 (Strem Chemicals,) (0.176 g, 0.19 mmol), Xphos (Strem Chemicals,) (181 mg, 0.38 mmol) and potassium phosphate tribasic (Fisher Scientific, Fair Lawn, N.J.) (2.45 g, 11.53 mmol) were added into the reaction mixture. The glass vessel was sealed and heated in a CEM Voyager Microwave (Matthews, N.C.; large-scale unit) at 110° C. for 20 min (50 watts, Powermax feature off). The mixture was diluted with DCM (50 mL) and filtered through AW Standard Super-Celt NF (Sigma-Aldrich). The filtrate was concentrated in-vacuo and the crude residue was diluted with DCM, then filtered through a fine-fritted funnel. The crude material was purified by chromatography through an Interchim PuriFlash UP pre-packed silica-gel column (Interchim INC, San Pedro, Calif.; 200 gram), eluted with a gradient of 0-8% EtOAc in CH2Cl2 (for recovery of the starting material, 8-bromo-N-(tert-butyl)-7-fluoro-3-methylquinoxalin-2-amine), then with a gradient of 0-5% MeOH in DCM, to provide 2-(3-(tert-butylamino)-6-fluoro-2-methylquinoxalin-5-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (286) (0.55 g, 1.50 mmol, 39% yield) as a tan solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 12.09 (br., 1H), 7.65 (dd, J=9.00, 5.87 Hz, 1H), 7.26-7.34 (m, 1H), 6.95-7.01 (m, 1H), 6.73-6.77 (m, 1H), 6.15 (s, 1H), 3.41-3.48 (m, 2H), 2.86 (t, J,=,6.85 Hz, 2H), 2.55 (s, 3H), 1.51 (s, 9H). m/z (ESI, +ve) 368 (M+H).

Provenance & Evidence