Phenyl vinyl sulfone → 6-Benzenesulfonyl-8-benzyl-1-phenyl-8-aza-bicyclo[3.2.1]oct-3-en-2-one

Participants

Reaction Steps

To 7.35 gm (21.5 mmol) 1-phenylmethyl-2-phenyl-3-hydroxypyridinium bromide in 20 ml of methanol was added 8.69 gm Amberlyst AG1-X8 resin —OH form 20–40 mesh. The mixture was stirred for a short period and then filtered and the resin washed with methanol. The solvent was removed in vacuo. The solid residue was taken up in toluene (150 ml) and treated with 50 mg of hydroquinone and 6.84 gm (37.1 mmol) phenyl vinylsulfone. The reaction mixture was heated under reflux for 18 hours and then cooled to room temperature. The solvent was removed in vacuo and the residue was chromatographed on silica gel eluting with 8:2/hexane:ethyl acetate to afford 5.87 gm (64%) of a light yellow solid. 1H NMR (CDCl3, 400 MHz) δ 7.71–7.61 (m, 5H), 7.46 (t, 2H, J=8 Hz), 7.37–7.23 (m, 8H), 6.84 (dd, 1H), J=9 Hz, J=5 Hz), 6.20 (d, 1H, J=9 Hz), 4.22 (d, 1H, J=5 Hz), 3.63 (d, 1H, J=14 Hz), 3.54 (dd, 1H, J=9 Hz, J=4 Hz), 3.40 (d, 1H, J=13 Hz), 2.80 (dd, 1H, J=15 Hz, J=3 Hz), 2.53 (dd, 1H, J=15 Hz, J=5 Hz) ppm. 13C NMR (CDCl3, 125 MHz) δ 196.9, 144.9, 138.3, 138.0, 137.7, 134.3, 130.9, 129.9, 129.8, 129.5, 129.2, 129.2, 129.0, 129.0, 128.9, 128.7, 128.2, 128.1, 127.9, 75.1, 66.3, 57.9, 49.1, 38.1 ppm. Mass spectrum APCI m/z 430 (p+1).

Provenance & Evidence