Hydrochloric Acid → 2,2-dimethyl-3-oxocyclobutanecarboxylic acid

Temperature

50 °C

To a solution of methyl 2,2-dimethyl-3-oxocyclobutanecarboxylate (1.0 equiv.) in MeOH (1.1 M) was added aqueous solution of sodium hydroxide (4.48 N, 2.0 equiv.), and the resulting mixture was stirred at 50° C. for 2 h. The starting material was consumed as monitored by thin layer chromatography, eluting with 20% ethyl acetate in petroleum ether. After removal of the volatile solvent, aqueous solution of hydrochloride (2 N, 1.4 equiv.) was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under vacuum to afford the product (88% yield) as a white solid, which was used for the next step without further purification. 1H NMR (300 MHz, DMSO-d6) δ (ppm) 12.4 (br, 1H), 3.31-3.23 (m, 1H), 3.17-3.08 (m, 1H), 2.97-2.91 (m, 1H), 1.22 (s, 3H), 1.04 (s, 3H).

1. customThe starting material was consumed
2. washeluting with 20% ethyl acetate in petroleum ether
3. additionwas added to the reaction mixture
4. extractionthe mixture was extracted with ethyl acetate
5. washThe combined organic layers were washed with brine
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationThe filtrate was concentrated under vacuum

ORD record

ord-38a9793c64ef455e8a84a9ee970864af

Source dataset

uspto-grants-2015_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09156798B2