Dimethyl Sulfoxide → HCID 59608023, compound

Participants

Reaction Steps

Oxalyl chloride (2.75 mL, 31.6 mmol, 3.0 equiv) in DCM (35 mL) was added dropwise to DMSO (3.00 mL, 42.1 mmol, 4.0 equiv) in DCM (35 mL) at −78° C. After 30 minutes, (S)-2-(3-chloropyrazin-2-ylamino)-1-((3aS,4S,6aR)-2,2-dimethyltetrahydro-3aH-cyclo-penta[d][1,3]dioxol-4-yl)ethanol (2-7) (3.30 g, 10.5 mmol, 1 equiv) in DCM (35 mL) was added dropwise. The resulting mixture was stirred at −78° C. for 1 hour, at which point triethylamine (6.60 mL, 47.3 mmol, 4.5 equiv) was added. The cooling bath was removed, and after 30 minutes the reaction mixture was concentrated. The resulting yellow residue was purified via flash chromatography on a silica gel column (ethyl acetate/hexanes) to yield 2-(3-chloropyrazin-2-ylamino)-1-((3aS,4R,6aR)-2,2-dimethyltetrahydro-3aH-cyclopenta[d][1,3]-dioxol-4-yl)ethanone (2-8) as a yellow solid. 1H NMR (500 MHz, CDCl3): δ 7.92 (d, J=2.7 Hz, 1H); 7.63 (d, J=2.7 Hz, 1H); 5.93 (s, 1H); 4.80 (d, J=5.7 Hz, 1H); 4.73 (t, J=5.4 Hz, 1H); 4.47 (dd, J=19.7, 5.0 Hz, 1H); 4.31 (dd, J=19.7, 4.7 Hz, 1H); 3.17 (d, J=8.1 Hz, 1H); 2.25-2.17 (m, 1H); 1.93-1.84 (m, 2H); 1.78-1.68 (m, 1H); 1.47 (s, 3H); 1.32 (s, 3H). LRMS m/z (M+H) 312.0 found, 312.1 required.

Provenance & Evidence