6-Aminophthalide → 2-(3-Oxo-1,3-dihydroisobenzofuran-5-ylamino)-6-(3-acetamidophenyl)pyrazine

Participants

Reaction Steps

Using Method L, 2-(3-acetamidophenyl)-6-chloropyrazine (4a) (60 mg, 0.24 mmol), 6-amino-1,3-dihydroisobenzofuran-1-one (52.2 mg, 0.35 mmol), Pd(0)2 dba3 (9 mg, 0.01 mmol), BINAP (50 mg, 0.04 mmol), sodium tert-butoxide (33 mg, 0.34 mmol) and toluene (5 mL) were reacted at 85° C. for 16 hours. The same workup as for Method L was followed by washing of the resulting solid with dichloromethane (30 mL) and filtration. The insoluble solid was then washed with acetone (60 mL). The acetone was evaporated under vacuo and the resulting solid was crystallised in cold dimethylformamide: dichloromethane mixtures to give 22.7 mg of title compound. Yield: 26.2%. 1 H NMR (250 MHz, DMSO-d6) δ 2.09 (s, 3 H), 5.39 (s, 2 H), 7.45 (t, 1 H, 8.0 Hz), 7.62-7.69 (m, 2 H), 7.76 (d, 1 H, 7.9 Hz), 8.23 (s, 1 H), 8.24-8.29 (m, 2 H), 8.39 (bs, 1 H), 8.50 (s, 1 H), 9.99 (s, 1 H), 10.06 (s, 1 H); 13C NMR (62.9 MHZ, DMSO-d6) δ 24.05, 69.78, 112.78, 117.31, 120.16, 121.13, 123.36, 124.58, 125.59, 129.29, 130.73, 133.63, 136.83, 139.71, 139.94, 141.47, 147.88, 151.05, 168.47, 170.75; m/z 361.2 [(M+H)+, calcd for C20H16N4O3 360.1].

Provenance & Evidence