Triphenyl phosphite → (S)-methyl 4-isopropyl-3-methyl-2-oxo-1,2,3,4-tetrahydropyrido[3,2-b]pyrazine-7-carboxylate

(S)-methyl 6-((1-ethoxy-1-oxopropan-2-yl)(isopropyl)amino)-5-nitronicotinate (0.900 g, 2.65 mmol) was dissolved in dichloromethane (10 mL). To this solution was added triphenyl phosphite (3.0 mg, 9.7 umol), ammonium metavanadate (30 mg, 0.265 mmol) and Pt/C (5% wt., 0.120 g). The reaction mixture was hydrogenated at 80 psi at 25° C. for 6 h. The mixture was filtered through a small pad of celite and the pad was washed with dichloromethane (20 mL). The combined filtrates were concentrated in vacuo and crystallized with ethyl ether to afford the title compounds as a white solid (0.658 g, 94%). 1H NMR (400 MHz, CHLOROFORM-d) δ (ppm): 1.33 (d, J=6.82 Hz, 3H) 1.36-1.41 (m, 6H) 3.90 (s, 3H) 4.34 (q, J=6.65 Hz, 1H) 4.86 (m, 1H) 7.52 (d, J=1.77 Hz, 1H) 8.59 (d, J=1.77 Hz, 1H) 8.73 (br. s., 1H); [M+H] calc'd for C13H17N3O3, 264. found 264.

1. filtrationThe mixture was filtered through a small pad of celite
2. washthe pad was washed with dichloromethane (20 mL)
3. concentrationThe combined filtrates were concentrated in vacuo
4. customcrystallized with ethyl ether

ORD-Eintrag

ord-caa4dae0da66465c8c53d1c612a7dc3d

Quelldatensatz

uspto-grants-2012_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08124606B2