Sodium borohydride → 3-Cyclohexyl-2-(4-methanesulfonyl-phenyl)-propionic acid methyl ester

Temperature

0 °C

A solution of nickel(II) chloride hexahydrate (157 mg, 0.66 mmol) and (E)-3-cyclohexyl-2-(4-methanesulfonyl-phenyl)-acrylic acid methyl ester (1.07 g, 3.31 mmol) in methanol (30 mL) was cooled to 0° C. and then treated with sodium borohydride (380 mg, 10 mmol) in four portions. After the addition, the black reaction mixture was stirred for 15 min at 0° C. and then allowed to warm to 25° C. where it was stirred for 15 h. The black solid was filtered using filter paper and washed with methanol. The combined solvents were concentrated in vacuo, and the residue was diluted with water (50 mL) and ethyl acetate (50 mL). The two layers were separated, and the aqueous layer was extracted with ethyl acetate (1×25 mL). The combined organic extracts were washed with a saturated aqueous sodium chloride solution (1×50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo to afford racemic 3-cyclohexyl-2-(4-methanesulfonyl-phenyl)-propionic acid methyl ester (1.04 g, 97%) as an amorphous white solid: EI-HRMS m/e calcd for C17H24O4S (M+) 324.1395, found 324.1395.

1. additionAfter the addition
2. temperatureto warm to 25° C. where it
3. stirringwas stirred for 15 h
4. filtrationThe black solid was filtered
5. filtrationusing filter paper
6. washwashed with methanol
7. concentrationThe combined solvents were concentrated in vacuo
8. additionthe residue was diluted with water (50 mL) and ethyl acetate (50 mL)
9. customThe two layers were separated
10. extractionthe aqueous layer was extracted with ethyl acetate (1×25 mL)
11. washThe combined organic extracts were washed with a saturated aqueous sodium chloride solution (1×50 mL)
12. dry with materialdried over anhydrous magnesium sulfate
13. filtrationfiltered
14. concentrationconcentrated in vacuo

ORD record

ord-8f5de7a96e5146ed9d5711e8c2afa1f8

Source dataset

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06610846B1