Lithiation of Trimethylsilylmethyl Phenyl Sulfide and Subsequent Reaction with Acetone

15 Lithiation of (Trimethylsilylmethyl) Phenyl Sulfide and Subsequent Reaction with Acetone 

A solution of 0.055 mol of butyllithium in 36 ml of hexane and 40 ml of THF are added together with cooling below 0°C. The mixture is cooled to — 10 °C, after which 0.05 mol (9.8 g) of (trimethylsilylmethyl) phenyl sulfide (see Exp. 14) is added. The cooling bath is removed. Above + 5 °C the reaction is markedly exothermic. After the evolution of heat has ceased, the yellow solution is warmed for an additional 10 min at 25 to 30 °C and subsequently cooled to — 60 °C. Dry acetone (0.06 mol, 3.5 g) is added in one portion after the cooling bath has been removed. The temperature of the solution rises within a few s to about 0 °C. After an additional 10 min 50 ml of ice water is added with vigorous stirring. After separation of the layers two extractions with small portions of Et20 are carried out The combined 

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