Water → 4,4-Dimethyl-1,2,3,4-tetrahydroquinoline

Temperature

50 °C

To 4,4-dimethyl-3,4-dihydro-1H-quinolin-2-one (7.6 g, 43 mmol) in THF (100 mL), was added lithium aluminum hydride (5 g, 134 mmole) portion wise with ice bath. The reaction mixture was warmed to 50° C. and stirred overnight. The reaction mixture was cooled to rt and treated with water (5 mL), 10% sodium hydroxide aqueous solution (5 mL) and water (15 mL). The resulting mixture was stirred for another 10 minutes. The mixture was filtered through Celite and the Celite was washed with ethyl acetate to a volume of approximately 50 mL. The resulting ethyl acetate solution was washed with brine (50 mL×2) and dried over MgSO4. Concentration of the filtrate and purification by silica gel column chromatography eluting with hexane/ethyl acetate (9/1) yielded 4,4-dimethyl-1,2,3,4-tetrahydro-quinoline 2-1 as a brown oil (6.0 g, 87% yield). MS: 162.0 (M+H)+; tR=1.47 min (method 1).

1. temperatureThe reaction mixture was cooled to rt
2. stirringThe resulting mixture was stirred for another 10 minutes
3. filtrationThe mixture was filtered through Celite
4. washthe Celite was washed with ethyl acetate to a volume of approximately 50 mL
5. washThe resulting ethyl acetate solution was washed with brine (50 mL×2)
6. dry with materialdried over MgSO4
7. customConcentration of the filtrate and purification by silica gel column chromatography
8. washeluting with hexane/ethyl acetate (9/1)

ORD record

ord-028023d919f54554b9271d4bdea67b55

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08263588B2