In a 100 ml flask containing a solution of 2.99 g (10 mmoles) of 2,6-bis-(1,1-dimethylethyl)-4-bromomethylphenol in 30 ml of DMF, 1.38 g (10 mmoles) of potassium carbonate and 2.07 g (10 mmoles) of 1-(4-nitrophenyl)piperazine are added successively. After agitation for two hours at ambient temperature, the reaction medium is diluted with 150 ml of dichloromethane and washed successively with 3×40 ml of water followed by 40 ml of brine. The organic solution is dried over sodium sulphate, filtered and concentrated under reduced pressure. The brown residue obtained is purified on a silica gel column (eluant:petroleum ether (B.p: 40-70° C.)/ ethyl acetate: 8/2). After concentration of the pure fractions, 2.31 g (54%) of a brown powder is obtained. Melting point: 177.5-178.5° C.
