Tetrahydrofuran → HCID 67267704, compound

Participants

Reaction Conditions

Reaction Steps

To a pre-cooled (0° C.) solution of methyltriphenylphosphonium bromide (286 mg, 0.8 mmol, 2 equiv) in THF (3 ml) was added n-butyllithium (0.49 ml of 1.6 M solution in hexanes, 0.78 mmol, 1.95 equiv) dropwise. The reaction mixture was stirred at 0° C. for 30 min. A solution of crude aldehyde 94 (ca 0.4 mmol) in THF (1.5 ml) was added and the mixture was stirred at 0° C. for 30 min and quenched with a saturated aqueous ammonium chloride solution (3 ml). The solvent was removed under reduced pressure, and the aqueous residue was extracted with ethyl acetate (3×3 ml). The combined organic extracts were dried over anhydrous sodium sulfate and concentrated in vacuo. Purification by flash column chromatography on silica (7% EtOAc/hexanes) afforded pure olefin 95 (96 mg, 73%) as a yellowish oil: [α]22D=−21.29 (c=0.7, CHCl3); TLC Rf=0.66 (silica gel, 33% EtOAc/hexanes); 1H NMR (600 MHz, CDCl3) δ 8.42 (s, 1H), 7.45-7.42 (dd, 1H, 3J=1.8 Hz, 2J=7.8 Hz), 7.19-7.17 (d, 1H, 3J=7.8 Hz), 5.95-5.88 (m, 1H), 5.14-5.11 (d, 1H, 3J=16.8 Hz), 5.05-5.02 (d, 1H, 3J=10.8 Hz), 4.54 (d, 1H, 3J=5.4 Hz), 2.97-2.93 (m, 1H), 2.74-2.68 (m, 1H), 2.6-2.56 (m, 1H), 2.3 (s, 3H), 1.96 (s, 3H), 0.99-0.96 (t, 9H, 3J=7.8 Hz), 0.67-0.62 (q, 6H, 3J=7.8 Hz); 13C NMR (100 MHz, CDCl3) δ 153.95, 149.82, 140.95, 139.83, 136.52, 134.99, 130.91, 122.40, 115.19, 87.15, 51.85, 39.15, 18.45, 13.44, 7.16, 5.49; HRMS calcd for C20H31NOSi+11+330.2253 found 330.2258 [M+H+].

Provenance & Evidence