5,6,7,8-Tetrahydro-1,8-naphthyridine-2-carbaldehyde → (5,6,7,8-Tetrahydro-1,8-naphthyridin-2-yl)methanol

Temperature

5 °C

A mixture of 5,6,7,8-tetrahydro-[1,8]naphthyridine-2-carboxaldehyde 1 (0.5 g) and lithhiumborohydride (3.0 mL, 2.0 M) in THF (5.0 ML) was stirred at 5° C. for 1 h. The reaction mixture was then allowed to warm to room temperature over a period of another hour, quenched with acetic acid (2.0 mL) and concentrated under reduced pressure. The residue was partitioned between 1N NaOH (20.0 mL)and EtOAc (25 mL). The organic phase was washed with brine (2×0 mL), dried (Na2SO4), and concentrated to dryness. The resulting residue was purified by silica gel flash chromatography using EtOAc containing 10% methanol to give 0.3 g of the title compound as a pale yellow solid: 1H-NMR δ (CD3OD) 7.18 (d, 1H, J=7.6 Hz), 6.58 (d, 1H, J=7.6 Hz), 4.40 (s, 2H), 3.34 (m, 2H), 2.69 (t, 2H, J=6.0 Hz), 1.85 (t, 2H, J=6.0 Hz); ES-MS, m/z =165 (MH+).

1. temperatureto warm to room temperature over a period of another hour
2. customquenched with acetic acid (2.0 mL)
3. concentrationconcentrated under reduced pressure
4. customThe residue was partitioned between 1N NaOH (20.0 mL)and EtOAc (25 mL)
5. washThe organic phase was washed with brine (2×0 mL)
6. dry with materialdried (Na2SO4)
7. concentrationconcentrated to dryness
8. customThe resulting residue was purified by silica gel flash chromatography

ORD record

ord-7a7d17e538b1412f8b8c16af5d934d6c

Source dataset

uspto-grants-2005_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06933304B2