4-Methyl-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione → 4-Methyl-1,7-bis(4-hydroxy-3-methoxyphenyl)heptane-3,5-dione

Participants

Reaction Steps

4-Methyl-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (6a, 0.20 g, 0.5 mmol) and palladium on activated carbon (0.25 g, 10%) were combined in ethyl acetate (100 ml). The mixture was placed under a hydrogen atmosphere (60 psi) on a Parr apparatus for 2 hr at room temperature. The resulting mixture was filtered through celite and the solvent evaporated to afford an oil. The crude oil was twice chromatographed on silica gel with ethyl acetate/hexane to give a semi-solid. The crude semi-solid was distilled bulb to bulb to give 80 mg (38%) of a pale yellow oil; 1H NMR: δ enol form: 1.69 (s, 3H), 2.72 (m, 8H), 3.83 (s, 6H), 5.48 (s, 2H), 6.69 (m, 4H), 6.79 (d, 2H, J=7.5 Hz); keto for: 1.23 (d, 3H, J=7.2 Hz), 2.72 (m, 8H), 3.57 (q, 1H, J=7.0 Hz), 3.83 (s, 6H), 5.48 (s, 2H), 6.69 (m, 4H), 6.79 (d, 2H, J=7.5 Hz); 13C NMR: δ 12.5, 29.2, 43.3, 55.9, 61.4, 111.0, 114.2, 120.7, 132.4, 143.9, 146.3, 206.1; Exact mass calcd for C22H26O6: 386.1729, observed (M+H) 387.1783.

Provenance & Evidence