[CH3:1][C:2]1[CH:7]=[C:6]([C:8]([CH3:11])([CH3:10])[CH3:9])[CH:5]=[C:4]([CH3:12])[C:3]=1[S:13](Cl)(=O)=O>O1CCCC1.[Zn].[Ti](Cl)(Cl)(Cl)Cl>[CH3:1][C:2]1[CH:7]=[C:6]([C:8]([CH3:11])([CH3:10])[CH3:9])[CH:5]=[C:4]([CH3:12])[C:3]=1[S:13][S:13][C:3]1[C:2]([CH3:1])=[CH:7][C:6]([C:8]([CH3:10])([CH3:9])[CH3:11])=[CH:5][C:4]=1[CH3:12]A two liter, three-neck flask, was obtained. A condenser with a drying tube, a thermometer, and a dropping funnel were each attached to the flask. Zinc dust (<10 micron, 43.6 g, 0.667 mol) and anhydrous tetrahydrofuran (400 mL) were added to the flask. The mixture was stirred and cooled on an ice-water bath and 58.6 ml (0.534 mmol) of titanium tetrachloride added drop wise (˜45 min). During the entire addition of titanium tetrachloride, the temperature of the mixture was maintained below 25° C. Once the addition was complete, a solution of 2,6-dimethyl-4-tert-butylbenzenesulfonyl chloride (69.48 g, 0.267 mol) in 200 mL of anhydrous tetrahydrofuran was added drop wise (˜60 min). During the entire addition of the material, the temperature of the mixture was maintained below 20° C. At the conclusion of the 2,6-dimethyl-4-tert-butylbenzenesulfonyl chloride addition, the ice-water bath was removed, the mixture was allowed to stir an additional 30 min. The mixture was then heated on an oil bath at 60° C. for 4 hours. The mixture was then cooled to room temperature and 800 mL of 1N hydrochloric acid and 300 mL of ice water added. The resultant pale yellow precipitates were collected by filtration and washed with water (300 mL×3). The precipitate was then dried under vacuum and the precipitates recrystallized from hexanes, giving 33.1 g bis(2,6-dimethyl-4-tert-butylphenyl) disulfide (see Formula III, Table 3). The yield of the reaction was 70% and the material had the following spectral data: 1H NMR (CDCl3) δ 7.04 (s, 4H, aromatic protons (Ar—H)), 2.23 (s, 12H, CH3), 1.30 (s, 18H, C(CH3)3).
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