Diisopropylamine → HCID 86709647, compound

Participants

Reaction Conditions

Reaction Steps

A solution of N,N-diisopropylamine (5.46 mL, 39 mmol) in anhydrous tetrahydrofuran (90 mL) was cooled to −10° C. before adding a solution of n-butyllithium (2.5 M in hexanes, 15 mL, 37.5 mmol) dropwise over 10 minutes maintaining the temperature below 0° C. The reaction mixture was stirred at 0° C. for 10 minutes before cooling to −78° C. A solution of (S)-4-benzyl-3-(3-cyclopropyl-propionyl)-oxazolidin-2-one (8.88 g, 32.5 mmol) in tetrahydrofuran (35 mL) was added dropwise over 10 minutes keeping the temperature below −70° C. The reaction mixture was stirred at −78° C. for 1 h then warmed to −15° C. for 2 h. The reaction mixture was diluted with saturated aqueous ammonium chloride solution (100 mL) and extracted with ethyl acetate (2×60 mL). The extract was dried over anhydrous sodium sulfate, filtered and evaporated to give a yellow gum. The gum was purified by silica gel chromatography using iso-hexanes/ethyl acetate 4:1 to yield the title compound (5.3 g, 52%) as a colourless oil. 1H NMR (300 MHz, CDCl3) δ 0.01-0.15 (m, 2H), 0.35-0.50 (m, 2H), 0.65-0.82 (m, 1H), 1.50-1.60 (m, 2H), 2.32-2.45 (m, 1H), 2.47-2.60 (m, 1H), 2.66-2.77 (m, 1H), 3.27-3.37 (m, 1H), 4.05-4.25 (m, 3H), 4.65-4.76 (m, 1H), 5.03-5.16 (m, 2H), 5.78-5.93 (m, 1H), 7.20-7.36 (m, 5H). LCMS (m/z) 314.1 [M+H], Tr=2.83 min.

Provenance & Evidence