Bromine → 3-Bromo-1,5-naphthyridine

Temperatur

80 °C

To a stirred mixture of 1,5-naphthyridine (C-1) (50.0 g, 384 mmol, 1.0 eq) and sodium acetate (62.9 g, 768 mmol, 2.0 eq) in acetic acid (300 mL) at 80° C., a solution of bromine (67.5 g, 422 mmol, 1.1 eq) in acetic acid (80 mL) was added dropwise while keeping the reaction temperature at 80° C. to 90° C. After stirring for 2 h at 80° C., the reaction was complete based on TLC analysis. The resulting mixture was cooled to RT and then filtered. The filtrate was concentrated in vacuo and the residue was purified by flash column chromatography on silica gel (0-30% ethyl acetate-petroether) to afford the desired product 3-bromo-1,5-naphthyridine (C-2) (36.5 g, 45% yield) as a pale yellow solid. 1H NMR (300 MHz, CDCl3-d6) δ: 8.97 (m, 2H), 8.57 (s, 1H), 8.37 (d, J=8.4 Hz, 1H), 7.65 (m, 1H); ESI-MS m/z: 208.96 [M+H]+.

1. customat 80° C. to 90° C
2. temperatureThe resulting mixture was cooled to RT
3. filtrationfiltered
4. concentrationThe filtrate was concentrated in vacuo
5. customthe residue was purified by flash column chromatography on silica gel (0-30% ethyl acetate-petroether)

ORD-Eintrag

ord-e74d6e03e2594d9aaa8c69d4b5618fd1

Quelldatensatz

uspto-grants-2015_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09096590B2