Trifluoroacetic acid → HCID 67498430, compound

To a stirred solution of 1-(tert-Butoxycarbonyl)-6-methyl-2-n-pentyl-1,2,3,4-tetrahydropyridine (1.0 g, 3.55 mmol) in 240 mL of CH2Cl2 was added sodium cyanoborohydride (1.34 g, 21.3 mmol). After being stirred 15 minutes at room temperature, the heterogeneous solution was cooled to −42° C. and TFA (3.5 mL, 35.53 mmol) was added slowly dropwise. After being stirred for 4 h at −42° C., the cold bath was removed, and the reaction mixture was immediately quenched with 200 mL of a saturated aqueous NaHCO3/THF mixture (50:50). The aqueous phase was extracted with CH2Cl2 (2×70 mL) and the combined organic extracts were washed with water and brine. The organic phase was dried with K2CO3, filtered through Celite, and evaporated to give crude product. Column chromatography using 5% EtOAc in hexanes gave 0.54 g (54%) of the product which was homogeneous by TLC analysis. 1H NMR (300 MHz) δ3.99-3.82 (m, 1 H), 3.79-3.74 (m, 1 H), 1.91-1.15 (m, 28 H), 0.92-0.83 (t, 3 H); 13C NMR (75 Mhz) 155.6 (s), 78.6 (s), 51.6 (s), 46.9 (s) 34.34 (s), 31.9 (s), 29.3 (s), 28.5 (s), 27.1 (s), 26.9 (s), 2.31 (s), 22.6 (s), 20.8 (s), 14.0 (s), 13.7 (s) ppm.

1. temperaturethe heterogeneous solution was cooled to −42° C.
2. stirringAfter being stirred for 4 h at −42° C.
3. customthe cold bath was removed
4. customthe reaction mixture was immediately quenched with 200 mL of a saturated aqueous NaHCO3/THF mixture (50:50)
5. extractionThe aqueous phase was extracted with CH2Cl2 (2×70 mL)
6. washthe combined organic extracts were washed with water and brine
7. dry with materialThe organic phase was dried with K2CO3
8. filtrationfiltered through Celite
9. customevaporated
10. customto give crude product

ORD record

ord-70c5c822775f43ac902d2415b8fcfbf0

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369078B1