Carbon Dioxide → Bicyclo[1.1.1]pentane-1-carboxylic acid, 3-methyl-

Participants

Reaction Steps

To a solution of 1-iodo-3-methylbicyclo[1.1.1]pentane (1.62 g, 7.79 mmol; prepared according to Eur. J. Org. Chem. 1137-1155 (2000)) in diethyl ether (26 mL), a solution of tert-butyllithium (9.16 mL, 15.57 mmol, 1.7 M in pentane) was added over a period of 40 min at −78° C. After stirring the reaction mixture for 1 h at this temperature, carbon dioxide gas was bubbled through the reaction mixture for 5 min and then the mixture was allowed to warm to room temperature. The reaction mixture was extracted twice with a 5% aqueous sodium bicarbonate solution. The combined aqueous phases were acidified to pH 2-3 with concentrated hydrochloric acid at 0° C., saturated with sodium chloride, and extracted with diethyl ether. The combined organic phases were dried and, after evaporation of the solvent under reduced pressure, purified by column chromatography (0-20% ethyl acetate in hexanes) to afford 3-methylbicyclo[1.1.1]pentane-1-carboxylic acid (0.5 g, 3.96 mmol, 50.9% yield); 1H NMR (400 MHz, DMSO-d6) δ ppm 12.21 (s, 1H), 1.82 (s, 6H), 1.14 (s, 3H).

Provenance & Evidence