2,3,4,4a,5,6-hexahydro-1H-pyrido[1,2-a]quinolone (R)-7

1H NMR (500 MHz, CDCl3): δ 7.82 (br s, 1H), 7.28-7.34 (m, 2H), 7.22-7.24 (m, 1H), 3.87 (m, 1H), 3.56 (m, 1H), 3.32 (m, 1H), 3.00-3.03 (m, 2H), 2.46-2.74 (m, 3H), 1.65-2.05 (m, 5H);

13C NMR (100 MHz, CDCl3): δ 137.6, 130.4, 129.2, 127.9, 124.1, 55.9, 54.5, 27.3, 25.2, 22.9, 20.3, 17.1;

Enantiomeric excess was determined by SFC: Chiralpak OD-3, 4.6 mm x 150 mm, particle size: 3 μm, temperature: 30 ºC, A: CO2, B: ethanol with 0.2% of isobutylamine, isocratic: A/B: 95/5, v/v, flow rate 3.0 mL/min.

HRMS (ESI) [M+H]+ m/z calcd for [C13H18N]+ is 188.1361 found 188.1429.

Synthesis of Enantioenriched 2‐Alkyl Piperidine Derivatives through
Asymmetric Reduction of Pyridinium Salts
Bo Qu,* Hari P. R. Mangunuru, Xudong Wei, Keith R. Fandrick, Jean-Nicolas Desrosiers, Joshua D.
Sieber, Dmitry Kurouski, Nizar Haddad, Lalith P. Samankumara, Heewon Lee, Jolaine Savoie, Shengli
Ma, Nelu Grinberg, Max Sarvestani, Nathan K. Yee, Jinhua J. Song and Chris H. Senanayake
Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc. 900 Ridgebury Road,
Ridgefield, CT 06877 USA
/////////////