A mixture of 1-iodo-4-trifluoromethoxy-benzene (3.56 g, 12 mmol), Pd(PPh3)4 (578 mg, 0.5 mmol) and cuprous iodide (95 mg, 0.5 mmol) in piperidine (40 ml) was degassed (Ar) and stirred for 30 min at 50° C. under an argon atmosphere. 2,2-Dimethyl-pent-4-yn-1-ol (1.25 g, 10 mmol, 90% purity) [Magnus, Philip; Slater, Martin J.; Principe, Lawrence M. Journal of Organic Chemistry (1989), 54(21), 5148-5153] in piperidine (20 ml) was added within 60 min at 50° C. During the addition the oil bath temperature was slowly raised to 80° C. starting after 30 min. The mixture was stirred for 2 h at this temperature. The reaction mixture was cooled to ambient temperature, poured into a solution of aqueous 10% KHSO4/ice water 1/1 and extracted two times with ether. The combined extracts were washed with aqueous 10% KHSO4 and aqueous 10% NaCl and dried over sodium sulfate. The solvent was removed under reduced pressure and the residue purified by flash chromatography (silica gel, heptane/AcOEt 2:1 to 1:1) to give 1.91 g (7 mmol, 70%) of the title compound as yellow oil.
