Carbon Dioxide → 5-tert-butylfuran-2-carboxylic Acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

n-Butyllithium (25 mL, 40 mmol, 1.6 M in hexane solution, 1.1 equiv) is added dropwise to a solution of 4.5 g of 2-t-butylfuran (36 mmol) in 60 mL of dry THF at −78° C. under N2. After 30 min, the cooling bath is replaced with an ice bath and the mixture stirred at 0° C. for 1 h. Dry CO2, generated from dry ice and dried over an anhydrous Na2SO4 tower, is bubbled into the reaction mixture over 20 min at −78° C. and then at 0° C. The reaction mixture is acidified with 1 M HCl to pH 1, then extracted with ethyl acetate. The organic layer is washed with brine, dried (NaSO4) and concentrated to give 4.2 g of 2-tertbutyl 5-furanoic acid as a pale yellow solid (69%). 1H NMR (CDCl3) d 11.0 (br s, 1H), 7.19 (d, 1H, J=3.3 Hz), 6.11 (d 1H, J=3.3 Hz), 1.29 (s, 9H).

Herkunft & Nachweise