Ammonium Chloride → Cyclohexyl(3-methylthieno[3,2-b]pyridin-2-yl)methanone

Temperature

0 °C

To a solution (50 mL) of 3-methylthieno[3,2-b]pyridine-2-carbaldehyde (2.24 g) synthesized above in tetrahydrofuran was added a 1.0M solution (18.9 mL) of cyclohexylmagnesium bromide in tetrahydrofuran at 0° C., and the mixture was stirred at 0° C. for 1.5 hr under argon atmosphere. Saturated aqueous ammonium chloride solution was added to quench the reaction, and the reaction mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (10-50% ethyl acetate/hexane) to give a pale-yellow oil. To a mixture of the obtained oil, 4-methylmorpholine N-oxide (1.81 g) and acetonitrile (40 mL) was added tetrapropylammonium perruthenate (238 mg), and the mixture was stirred at room temperature for 2 hr, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (0-30% ethyl acetate/hexane) to give the title object compound (1.38 g, 79%) as a colorless oil.

1. customto quench
2. customthe reaction
3. extractionthe reaction mixture was extracted with ethyl acetate
4. washThe extract was washed with saturated brine
5. dry with materialdried over magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel column chromatography (10-50% ethyl acetate/hexane)
8. customto give a pale-yellow oil
9. stirringthe mixture was stirred at room temperature for 2 hr
10. concentrationconcentrated under reduced pressure
11. customThe residue was purified by silica gel column chromatography (0-30% ethyl acetate/hexane)

ORD record

ord-798d505a96504b2392f43911b249be03

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08436043B2