反应详情

To a stirred suspension of Step 2 intermediate (1.90 g, 6.571 mmol) in acetonitrile (40 mL) was added triphenylphosphine (1.89 g, 7.228 mmol) at room temperature. The resulting reaction mixture was slowly heated to reflux overnight. The solvent was concentrated in vacuo and the residue was stirred with diisopropyl ether and filtered. The solid was dried under vacuum to afford 3.90 g of the product as an off-white solid: 1H NMR (300 MHz, DMSO-d6) δ 1.17 (t, J=7.2 Hz, 3H), 4.08 (q, J=6.9 Hz, 2H), 5.35 (s, 1H), 5.40 (s, 1H), 7.20-7.22 (m, 1H), 7.37 (br s, 1H), 7.50 (d, J=4.5 Hz, 1H), 7.68-7.76 (m, 10H), 7.81-7.87 (m, 3H), 7.99 (d, J=3.9 Hz, 1H); ESI-MS (m/z) 471.24 (MH)+.

1. customThe resulting reaction mixture
2. temperaturewas slowly heated
3. temperatureto reflux overnight
4. concentrationThe solvent was concentrated in vacuo
5. filtrationfiltered
6. customThe solid was dried under vacuum