Sulfuric Acid → HCID 45788797, compound

To 3-(6-aminopyridin-3-yl)pentane-1,5-diol/toluene mixture (1.96 g, 10 mmol in 40 mL) were added 1 mL water to help dissolving, and then conc. H2SO4 (98%, 1.6 mL, 30 mmol). The resulting mixture was heated to reflux with Dean-Stark to remove water from reaction mixture for 1 h 20 min. The reaction mixture was cooled down to room temperature, and concentrated. The residue was diluted with ice cold water (15 mL), neutralized by solid Na2CO3 (4 g), and extracted with EtOAc (3×30 mL). The EtOAc extracts were combined, washed with brine (30 mL), dried over Na2SO4, and concentrated. A light yellow solid was obtained as crude 5-(tetrahydro-2H-pyran-4-yl)pyridin-2-amine. LCMS (m/z) 179.2 (MH+) 0.33 min; 1H NMR (CDCl3) δ ppm 7.95 (d, J=2.0 Hz, 1H), 7.32 (dd, J=8.2, 2.3 Hz, 1H), 6.49 (d, J=8.2 Hz, 1H), 4.34 (br. s., 2H), 4.11-3.99 (m, 2H), 3.51 (td, J=11.2, 3.3 Hz, 2H), 2.73-2.56 (m, 1H), 1.75-1.69 (m, 4H).

1. dissolutionto help dissolving
2. temperatureThe resulting mixture was heated
3. temperatureto reflux with Dean-Stark
4. customto remove water
5. customfrom reaction mixture for 1 h 20 min
6. concentrationconcentrated
7. additionThe residue was diluted with ice cold water (15 mL)
8. extractionextracted with EtOAc (3×30 mL)
9. washwashed with brine (30 mL)
10. dry with materialdried over Na2SO4
11. concentrationconcentrated

ORD record

ord-6262018c7fe24152a7475584f8d82af0

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09242996B2