Methanol → Methyl camphorate

Participants

Reaction Conditions

Reaction Steps

To a solution of (1S,3R)-1,2,2-trimethylcyclopentane-1,3-dicarboxylic acid (5.1 g, 25.5 mmol) in methanol (63.7 ml) at −78° C. was added thionyl chloride (2.045 ml, 28.0 mmol). After stirring at −78° C. for 30 minutes, the reaction was allowed to warm to room temperature. Stirring was continued for 14 hrs. The reaction mixture was concentrated under reduced pressure, yielding a yellow oil. The oil was taken into water. The solution was adjusted to pH 12 with 1.0 N NaOH and was washed with ethyl acetate. The basic aqueous layer was acidified with 1.0 N HCl, and was extracted with ethyl acetate (3×, 100 ml). The ethyl acetate extracts were combined, dried with sodium sulfate, filtered, and concentrated under reduced pressure to afford (1S,3R)-3-(methoxycarbonyl)-1,2,2-trimethylcyclopentanecarboxylic acid (5.35 g, 24.97 mmol, 98% yield) as a colorless oil. ESI-MS m/z 237.1 ([M+H]+).

Provenance & Evidence