[CH2:1]=[C:2]1[O:6][C:5](=[O:7])[CH:4]=[C:3]1[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1.CCOC(C)=O.C(Cl)Cl>C(O)C.[Pd]>[CH3:1][CH:2]1[O:6][C:5](=[O:7])[CH:4]=[C:3]1[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1A solution of 5-methylene-4-phenyl-2(5H)furanone (2.63 mmol) in ethanol (50 mL) containing Pd—C (25 mgs; 5%) was hydrogenated under an atmosphere of hydrogen at room temperature for 24 hr. The catalyst was filtered off using a pad of Celite and the solvent evaporated in vacuo, leaving a colourless semi-solid, which upon flash chromatography using (EtOAc, CH2Cl2; 1:5) as the eluent gave 5-methyl-4-phenyl-2(5H)furanone 27 as a semi-solid in 90% yield. 1H NMR: δ(CDCl3) 3.33 (d, J 4 Hz, 3H, C5-Me), 5.56 (q, J 4 Hz, 1H, C5-H), 6.26 (s, 1H, C3-H) and 7.47 (s, 5H, Ar H's). 13C NMR: 19.71, 65.85, 66.39, 113.67, 127.11, 129.14, 129.87, 131.20 168.79, 172.54.
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