Ethyl bromoacetate → tert-Butyl (3R)-6-cyclohexyl-3-{3-[(2-ethoxy-2-oxoethoxy)methyl]-1,2,4-oxadiazol-5-yl}hexanoate

Participants

Reaction Conditions

Reaction Steps

A suspension of sodium hydride 60% suspension in mineral oil (13 mg, 0.33 mmol) in anhydrous tetrahydrofuran (1 ml) was cooled to 0° C. and treated with a solution of tert-butyl (3R)-6-cyclohexyl-3-[3-(hydroxymethyl)-1,2,4-oxadiazol-5-yl]hexanoate (Preparation 85) (105 mg, 0.30 mmol) in anhydrous tetrahydrofuran (1 ml) and stirred under a nitrogen atmosphere for 1 hour. Ethyl bromoacetate (37 μl, 0.33 mmol) was added and the mixture was stirred for 18 hours, being allowed to warm to room temperature over this time. The reaction mixture was diluted with ethyl acetate and washed with water and brine, dried over anhydrous sodium sulphate, filtered and the solvent removed under reduced pressure. The solid was purified by column chromatography on silica gel eluting with a gradient system of pentane:ethyl acetate (99:1) to pentane:ethyl acetate (80:20) to afford the title compound as a colourless oil (84 mg).

Provenance & Evidence