p-Toluenesulfonic acid → 2(5H)-Furanone, 3-(4-fluorophenyl)-4-[4-(methylsulfonyl)phenyl]-

Participants

Reaction Steps

Under nitrogen, 4.10 g (11.7 mmol) of 2-(4-fluorophenyl)-1-[2-[4-(methylsulfonyl)phenyl]-2-oxoethoxy]ethanone (prepared in Step 4), 6.52 mL (46.8 mmol) of triethylamine, 4.89 g (25.7 mmol) of p-toluenesulfonic acid, and 12 g of 4Å molecular sieves were added to 117 mL of acetonitrile and stirred at reflux for 16 hours. The reaction mixture was concentrated in vacuo and the residue partitioned between dichloromethane and water. The dichloromethane layer was dried (MgSO4) and reconcentrated in vacuo. Recrystallization from hexane/ethyl acetate (2:1) gave 3.65 g (94%) of 3-(4-fluorophenyl)-4-[4-(methylsulfonyl)phenyl]-5H-furan-2-one as a solid: mp 166°-167° C.; NMR (CDCl3) δ3.08 (s, 3H), 5.19 (s, 2H), 7.10 (t, J=9 Hz, 2H), 7.42 (dd, J=6 and 9 Hz, 2H), 7.52 (d, J=9 Hz, 2H), 7.97 (d, J=9 Hz, 2H); HRMS. Calc'd for C17H13FO45 : 332.0519. Found: 332.0501. Anal. Calc'd for C17H13FO45 : C, 61.44; H, 3.94; O, 19.26. Found: C, 61.11; H, 4.06; 0, 19.32.

Provenance & Evidence