3-Quinolin-3-ylprop-2-yn-1-ol → 3-(Quinolin-3-yl)prop-2-en-1-ol

To a dry, jacketed 250-mL three-necked round-bottom flask was charged sodium bis(2-methoxyethoxy)aluminum hydride (Red-Al, 70% wt. solution in toluene, 11.0 g, 38.1 mmol, 1.39 eq) and anhydrous THF (20 mL). To this precooled (0-2° C.) and magnetically stirred solution was added a THF (50 mL) solution of the 3-(3-quinolyl)-2-propyn-1-ol (5.0 g, 27.32 mmol) via pressure equalizing dropping funnel. The temperature was not allowed to rise above 15° C. After the addition was complete (20 minutes) the mixture was allowed to warm up to room temperature and stirred for one hour. The solution was then cooled to 0° C. and quenched by the addition of aqueous 10% sulfuric acid (20 mL) such that the internal temperature did not rise above 15° C. The biphasic reaction mixture was then washed with ethyl acetate (3×100 mL). The pH of the aqueous acidic product solution was then adjusted to pH 9-10 with aq. conc. NH4OH and back extracted into ethyl acetate (2×125 mL). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give exclusively 3-(3-quinolyl) trans-2-propen-1-ol as a solid: 4.1 g, 81%.

1. custom(0-2° C.) and magnetically stirred solution
2. customto rise above 15° C
3. additionAfter the addition
4. custom(20 minutes)
5. temperatureThe solution was then cooled to 0° C.
6. customquenched by the addition of aqueous 10% sulfuric acid (20 mL) such that the internal temperature
7. customdid not rise above 15° C
8. customThe biphasic reaction mixture
9. washwas then washed with ethyl acetate (3×100 mL)
10. extractionback extracted into ethyl acetate (2×125 mL)
11. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
12. filtrationfiltered
13. concentrationconcentrated under reduced pressure

ORD record

ord-e7c8c790e8bc4eeabcc67e6d0e34587e

Source dataset

uspto-grants-2003_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06579986B2