反应详情

A solution of ethyl 5-{(1R)-1-[2-(tert-butoxy)-2-oxoethyl]-4-cyclohexylbutyl}-1,2,4-oxadiazole-3-carboxylate (Preparation 3) (820 mg, 2.08 mmol) in dichloromethane (10 ml) was cooled to 0° C. and treated with trifluoroacetic acid (5 ml). The mixture was stirred for 2.5 hours being allowed to warm to room temperature over this time. The solvent was removed under reduced pressure and the residue azeotroped with toluene (×2). The residue was then dissolved in ethyl acetate, washed sequentially with an aqueous solution of sodium dihydrogen citrate and brine, dried over anhydrous sodium sulphate, filtered and the solvent removed under reduced pressure to afford the title compound as an oil (740 mg).

1. customThe solvent was removed under reduced pressure
2. customthe residue azeotroped with toluene (×2)
3. dissolutionThe residue was then dissolved in ethyl acetate
4. washwashed sequentially with an aqueous solution of sodium dihydrogen citrate and brine
5. dry with materialdried over anhydrous sodium sulphate
6. filtrationfiltered
7. customthe solvent removed under reduced pressure