3-Methyl-2-furoic acid → 3-Methyloxolane-2-carboxylic acid

3-Methyl-2-furoic acid (5 g) in ethyl acetate (100 ml) and 5% rhodium on charcoal catalyst (0.5 g) were hydrogenated at ambient temperature and the atmosphere for 6-7 h. The catalyst was filtered off and replaced with a further quantity (1 g) of catalyst. The reaction mixture was hydrogenated for a further 7 h. This procedure was repeated again until no more hydrogen was absorbed. After filtration through kieselguhr and removal of solvent under reduced pressure, the title compound was obtained as a colourless oil (5.096 g, quant.); νmax (CH2Cl2) 3674, 3377(br), 1770 and 1722 cm-1 ; δH (CHC13) 1.08 (3 H, d, J 7.1 Hz), 1.72 (1 H, m), 2.16 (1 H, m), 2.68 (1 H, m), 3.94 (1 H, m), 4.18 (1 H, m), 4.47 (1 H, d, J 7.5 Hz) and 9.42 (1 H, v. br s, exch). [Mass spectrum: +ve ion (ammonia) MNH4+ (148)].

1. customwere hydrogenated at ambient temperature
2. filtrationThe catalyst was filtered off
3. waitThe reaction mixture was hydrogenated for a further 7 h
4. customwas absorbed
5. filtrationAfter filtration
6. customthrough kieselguhr and removal of solvent under reduced pressure

ORD record

ord-a7a59f1b03b54197864b0e6355ec875e

Source dataset

uspto-grants-1999_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06001997