To a degassed (argon) solution of 3.56 g (12.00 mmol) 1-iodo-4-trifluoromethoxy-benzene in 40 ml piperidine was added 0.58 g (0.50 mmol) Pd(PPh3)4 and 0.095 g. (0.50 mmol) CuI. The reaction mixture was stirred at 50° C. for 10 min, then 1.25 g (10.00 mmol) of above synthesized 2,2-dimethyl-pent-4-yn-1-ol in 20 ml of piperidine was added dropwise within 1 h. During the addition the oil bath was slowly heated to 80° C. starting after 30 min. The reaction mixture was stirred at this temperature for 2 h and then extracted with chilled aqueous 10% KHSO4/ether (three times). The organic phases were washed with aqueous 10% NaCl, dried (Na2SO4) and evaporated. Purification by flash-chromatography on silica gel (n-heptane/EtOAc 2:1 to 1:1) yielded 1.91 g of the title compound as a yellow oil.
