3-Oxo-cyclopentanecarboxylic acid methyl ester → Cyclopentanecarboxylic acid, 3-hydroxy-, methyl ester

Sodium borohydride (442.6 mg, 11.70 mmol) was added portionwise to a solution of methyl 3-oxocyclopentane-carboxylate A-10 (1.66 g, 11.70 mmol) in absolute ethanol (42.0 mL) at 0° C. The reaction mixture was allowed to warm to room temperature and stirred for 90 mins, then quenched slowly with a 1 N aqueous solution of hydrogen chloride (10 mL), and concentrated to ca. 15 mL under reduced pressure. The aqueous layer was extracted with methylene chloride (3×50 mL); the combined extracts were dried over anhydrous magnesium sulfate, filtered and concentrated to dryness under reduced pressure to give crude methyl 3-hydroxycyclopentanecarboxylate A-11 as a yellow oil (1.33 g, Yield=79%). This material was used for next step without purification. MS (ESI), [M+1]+ 145.

1. customat 0° C
2. customquenched slowly with a 1 N aqueous solution of hydrogen chloride (10 mL)
3. concentrationconcentrated to ca. 15 mL under reduced pressure
4. extractionThe aqueous layer was extracted with methylene chloride (3×50 mL)
5. dry with materialthe combined extracts were dried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated to dryness under reduced pressure

ORD-Eintrag

ord-58b00e8704be473d918b838ff296efb7

Quelldatensatz

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08637507B2