4-Bromothiophenol → 1-Bromo-4-cyclopropylthiobenzene

To a degassed solution of potassium tert-butoxide (2.08 g, 18.51 mmol) in dry dimethylsulphoxide (6 mL), 4-bromo-benzenethiol (3.5 g, 18.5 mmol) was added and the mixture was stirred for 15 min at ambient temperature under nitrogen. Bromocyclopropane (4.4 mL, 55.5 mmol) was added afterwards and the reaction mixture was heated at 80° C. for 24 h in a sealed vessel. The mixture was cooled, diluted with ether (150 mL) and washed with water (100 mL). The aqueous layer was extracted with ether (3×50 mL). Combined organic extracts were finally dried with anhydrous magnesium sulfate. 1-Bromo-4-cyclopropylsulfanyl-benzene was obtained after evaporation of the solvent as yellow liquid.