[H-].[Na+].[OH:3][C:4]1[C:13]([CH:14]=[C:15]([CH3:17])[CH3:16])=[CH:12][CH:11]=[CH:10][C:5]=1[C:6]([O:8][CH3:9])=[O:7].[CH3:18][N:19]([CH3:23])[C:20](Cl)=[S:21]>CN(C)C=O>[CH3:18][N:19]([C:20](=[S:21])[O:3][C:4]1[C:13]([CH2:14][C:15]([CH3:17])=[CH2:16])=[CH:12][CH:11]=[CH:10][C:5]=1[C:6]([O:8][CH3:9])=[O:7])[CH3:23]To 1 liter of dry dimethylformamide were added 16 g of 60% sodium hydride in oil. After stirring under a nitrogen atmosphere, 81.7 g of 2-hydroxy-3-(2-methylpropenyl)benzoic acid, methyl ester, as a solution in dimethylformamide, were added in dropwise fashion. After stirring at room temperature, a solution 49.6 g of dimethylthiocarbamoyl chloride in dimethylformamide was added over a one hour period. The reaction mixture was stirred at room temperature overnight, then poured onto ice and extracted with diethyl ether and ethyl acetate. The combined organic extracts were washed successively with a 10% sodium hydroxide solution and water, dried over sodium sulfate, and concentrated in vacuo. The residue was vacuum distilled, and the fraction distilling at 162°-168° C. and 0.6 torr provided 69.9 g of the desired subtitle intermediate. NMR, MS.
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