Acetovanillone → (E)-1,5-bis-(4-hydroxy-3-methoxyphenyl)-pent-4-ene-1,3-dione

Participants

Reaction Steps

By a similar procedure as described in Example 1 using 1-(4-hydroxy-3-methoxyphenyl)-butane-1,3-dione (prepared by reaction of 4-hydroxy-3-methoxyacetophenone with ethyl acetate in the presence of sodium hydride) in place of 5,5-dimethylhexane-2,4-dione, (E)-1,5-bis-(4-hydroxy-3-methoxyphenyl)-pent-4-ene-1,3-dione (920 mg, 39%) was obtained as yellow needles: mp 170-172° C.; LRMS m/z 342 (M+); 1H NMR (500 MHz, CDCl3) δ 3.95 (3H, s, OCH3), 3.98 (3H, s, OCH3), 5.85 (1H, brs, OH), 6.04 (1H, brs, OH), 6.26 (1H, s, H-2), 6.48 (1H, d, J=15.7 Hz, H-4), 6.94 (1H, d, J=7.2 Hz, H-5″), 6.97 (1H, d, J=8.3 Hz, H-5′), 7.05 (1H, brs, H-2″), 7.12 (1H, brd, J=8.3 Hz, H-6″), 7.51 (1H, brd, J=7.2 Hz, H-6′), 7.56 (1H, brs, H-2′), 7.60 (1H, J=15.7 Hz, H-5), 16.2 (1H, brs, OH) ppm; TLC Rf=0.5 (silica, dichloromethane); HPLC Rt 14 min 99.6% purity.

Provenance & Evidence