Water → Bis(9,9'-spirobifluoren-2-yl)sulfoxide

Participants

Reaction Conditions

Reaction Steps

110 ml (275 mmol) of an n-butyllithium solution (2.5 M in hexane) were added dropwise to a suspension, cooled to −78° C., of 98.8 g (250 mmol) of 2-bromo-9,9′-spirobifluorene in 1500 ml of THF at such a rate that the temperature did not rise above −65° C. The reaction mixture was stirred at −78° C. for 3 h and then admixed dropwise with a mixture of 7.2 ml (125 mmol) of thionyl chloride and 300 ml of THF, and subsequently stirred at −78° C. for a further 3 h. After the reaction mixture had been warmed to room temperature, the reaction mixture was admixed with 25 ml of water and concentrated to dryness under reduced pressure. The residue was taken up in 1000 ml of dioxane and 500 ml of water, and the organic phase was removed, washed once more with 500 ml of water and subsequently dried over magnesium sulfate. Subsequently, the solid which remained after concentration of the organic phase was recrystallized five times from dioxane (1 g/ml) and then sublimed under high vacuum (T=370° C., p=5×10−5 mbar). The yield at a purity of >99.9% by HPLC was 114.0 g (168 mmol), corresponding to 67.2% of theory.

Provenance & Evidence