Allyl iodide → Butyl 1-allylcyclopropane-1-sulfonate

To a solution of 1-butyl cyclopropanesulfonate (4.8 g, 24.9 mmol) in THF at −78° C. was added simultaneously butyllithium solution (15.6 ml, 24.9 mmol, 1.6M, THF) and allyl iodide (24.9 mmol) under nitrogen atmosphere. The reaction mixture was stirred 2 hours at −78° C. and 3 hours at room temperature. The volatiles were evaporated under reduced pressure and the residue extracted with CH2Cl2 (100 ml). The extract was washed with water, dried (MgSO4) and evaporated. The residue was purified over silica gel chromatography (eluants: hexane/CH2Cl2) to obtain the titled product (3.75 g, 69.0%) as a colorless oil, 1H NMR (300 MHz, CDCl3): δ 5.6 (m, 1H), 5.13-5.08 (t, 2H), 4.21 (t, 2H), 2.65 (d, 2H), 1.7 (m, 2H), 1.4 (m, 4H), 0.93 (m, 5H).