N-bromobutanimide → 6-Bromo-7-(dimethoxymethyl)-1,2,3,4-tetrahydro-1,8-naphthyridine

Temperature

25 °C

Into a 3 l 4-necked round-bottom flask was placed 7-(dimethoxymethyl)-1,2,3,4-tetrahydro-1,8-naphthyridine (intermediate 4, 114.6 g, 550.3 mmol) in acetonitrile (2 l). This was followed by the addition of NBS (103 g, 578 mol) in portions with stirring at 25° C. The resulting solution was stirred for 30 min at 25° C. The resulting mixture was concentrated under vacuum and the residue was diluted with 1000 ml of diethylether. The mixture was washed with 3×100 ml of ice/water. The aqueous phase was extracted with 2×100 ml of diethylether and the organic layers were combined. The resulting mixture was washed with 1×100 ml of brine, dried over sodium sulfate and concentrated under vacuum to give the title compound as a light yellow solid. LC-MS: (ES, m/z):

1. customInto a 3 l 4-necked round-bottom flask was placed
2. stirringThe resulting solution was stirred for 30 min at 25° C
3. concentrationThe resulting mixture was concentrated under vacuum
4. additionthe residue was diluted with 1000 ml of diethylether
5. washThe mixture was washed with 3×100 ml of ice/water
6. extractionThe aqueous phase was extracted with 2×100 ml of diethylether
7. washThe resulting mixture was washed with 1×100 ml of brine
8. dry with materialdried over sodium sulfate
9. concentrationconcentrated under vacuum

ORD record

ord-5927056831f647e090588864678ecdac

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09266883B2