C1(C)C=CC=CC=1.N1CCCCC1.[C:14]1([CH2:20][CH2:21][C:22](=[CH2:26])[C:23]([OH:25])=[O:24])[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.[S:27]1C=CC=C1CC(O)=O.[CH3:36][CH2:37][O:38]CC>>[C:37]([S:27][CH2:26][CH:22]([CH2:21][CH2:20][C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1)[C:23]([OH:25])=[O:24])(=[O:38])[CH3:36]A 250 mL round bottomed flask, fitted with a Teflon magnetic stirring bar and a reflux condenser, was filled with 150 mL of toluene, 0.5 mL piperidine and 8.6 g (49 mmole) of 4-phenyl-2-methylenebutyric acid. Then 4.1 g (54 mmole) of thiolacetic acid was added to the solution and the mixture heated to reflux for 8 hours under nitrogen. 1H-NMR analysis of the reaction mixture indicated some starting material remained. Another 1 g of thiolacetic acid was added and the mixture stirred at reflux for an additional 4 hours. By 1H-NMR, all of the starting material was seen to have reacted. The solution was cooled to 5° C., and 100 mL of ether added to the mixture. The excess thiolacetic acid was removed by extraction (3×50 mL 2% sodium bicarbonate). Then 50 mL of 1N HCl was added to the organic layer and the solution shaken vigorously. The organic layer was separated and dried over MgSO4. The solution was filtered and the solvent removed under reduced pressure. Recovered 10.0 g of product (81% yield).
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