2,5-Hexanedione → HCID 54115734, compound

Participants

Reaction Steps

Thionyl chloride (25 mL, 0.34 mol) was added dropwise to ethanol (540 mL). The reaction was heated to reflux for 15 minutes and cooled. The solution was treated with 2-[4-aminosulfonylphenyl]-1-phenyl-ethan-1-one from Step 1 (20.0 g, 72.64 mmol) and acetonylacetone (12.8 mL, 108.96 mmol), and reheated to reflux for 30 minutes. After cooling to room temperature, the solution was poured into rapidly stirred saturated aqueous Na2CO3 and ice (1500 mL). The aqueous phase was extracted with ethyl acetate (2×700 mL). The combined organics were washed with brine, dried over MgSO4, filtered and concentrated in vacuo, yielding a brown oil. The oil was diluted with ethyl acetate (200 mL) and hexane (2000 mL), dried with MgSO4, gravity filtered, then purified through a short silica gel column with hexane and ethyl acetate (1:1) as eluant. The material was concentrated in vacuo and crystallized from hexane/ethyl acetate. The solid was isolated by filtration and air dried to afford 2,5-dimethyl-1-[[4-(2-oxo-2-phenylethyl)phenyl]sulfonyl]-1H-pyrrole (12.2 g, 49%) as a brown solid: mp 94.6°-98.8° C. 1H NMR (DMSO-d6 /300 MHz) 8.05 (d, J=7.25 Hz, 2H), 7.76 (d, J=8.26 Hz, 2H), 7.65 (t, J=7.85 Hz, 1H), 7.54 (t, J=7.85 Hz, 1H), 7.44 (d, J=8.26 Hz, 2H), 7.30 (br s, 2H), 4.52 (s, 2H). Mass spectrum: M+H obs. at m/z=354.

Provenance & Evidence