Isobutyric Acid → HCID 123850736, compound

Participants

Reaction Steps

To the stirred solution of hydrochloride salt of 5′-(4,4,4-trifluoro-3-(3,4,5-trichlorophenyl)but-2-enoyl)-3′H-spiro[azetidine-3,1′-isobenzofuran](Preparation 26, 1.0 g, 2.2 mmol, 1 eq) in DMF (10 mL) was added Et3N (2.4 mL, 17.3mmol, 8 eq) followed by addition of iso-butyric acid (0.38 g, 4.32mmol, 2 eq), HOBt (0.29 g, 2.16 mmol, 1 eq) and EDC.HCl (0.62 g, 3.24 mmol, 1.5 eq) at room temperature. Resulting reaction mixture was stirred at room temperature for 18 hours under nitrogen atmosphere. After consumption of starting material, reaction mixture was quenched by water (30 mL) and extracted with ethyl acetate (3×25 mL). Combined organic layer was washed with aqueous sodium bicarbonate (50 mL), aqueous LiCl solution (2×50 mL), brine (50 mL) and dried over sodium sulfate. Organic layer was concentrated in vacuo to get brown sticky oil (1.0 g, Crude). Purification was done by Combiflash chromatography using 40 g Redisep column. Compound was eluted in 40% ethyl acetate in n-hexane to get title compound as off white solid (0.5 g, 43%). 1H NMR (400 MHz, CDCl3) δ: 1.13-1.17 (m, 6H), 2.46-2.53 (m, 1H), 4.25 (d, J=10.64 Hz, 1H), 4.30-4.34 (m, 2H), 4.52 (d, J=9.32 Hz, 1H), 5.15 (s, 2H), 7.27 (s, 2H), 7.40 (d, J=1.36 Hz, 1H), 7.49 (d, J=8.04 Hz, 1H), 7.68 (s, 1H), 7.84 (d, J=7.92 Hz, 1H). LC-MS (m/z): 531.9 (M+H).

Provenance & Evidence