Bromide ion → HCID 178447107, compound

Participants

Reaction Conditions

Reaction Steps

While under a nitrogen atmosphere, a solution of cis-4-[2-(4-chlorophenyl)-[1,3]-dioxolan-2-yl]-cyclohexanecarboxylic acid, methoxy-methyl amide (1.36 g, 3.85 mmol), in tetrahydrofuran (10 mL) was cooled to 0° C. and treated with 4-butenylmagnesiun bromide (0.5 M in THF, 19.24 mL, 9.62 mmol) in a dropwise manner. The solution was stirred for 1 hour at 0° C. then allowed to warm to room temperature overnight. The resulting solution was poured into water, acidified to pH 3-4 with 1 N hydrochloric acid, and extracted with ethyl acetate (3×). The combined organic phase was washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Purification by flash column chromatography (silica gel, 0-25% ethyl acetate in heptane) gave cis-1-{4-[2-(4-chlorophenyl)-[1,3]-dioxolan-2-yl]-cyclohexyl}pent-4-en-1-one as a colorless oil (1.13 g, 84%); 1H NMR (CDCl3, 300 MHz) δ 7.31 (d, J=7.5 Hz, 2H), 7.27 (d, J=7.5 Hz, 2H), 5.78 (m, 1H), 4.96 (m, 2H), 3.94 (m, 2H), 3.68 (m, 2H), 2.50 (m, 3H), 2.30 (m, 2H), 2.15 (dd, J=13, 3 Hz, 2H), 1.76 (tt, J=11, 3 Hz, 1H), 1.36-1.56 (m, 4H) and 1.25 (td, J=13, 3 Hz, 2H); MS (+CI): m/z for C20H25ClO3: expected 348.2. found 349.2 (M+H)+.

Provenance & Evidence