The mixture of 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)-hex-4-en-1-ol and 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-3-methyl-2-(trifluoromethyl)pent-4-en-1-ol (4.6 g, 13.84 mmol) is dissolved in ethanol (100 ml). Following addition of 10% Pd/carbon (0.7 g) hydrogen is introduced into the reaction mixture for four hours via a balloon. The catalyst is filtered off with suction (glass fibre filter) and the precipitate is washed with ethanol. Following removal of the solvent on a rotary evaporator, the residue (4.59 g, 99.2%) is used in crude form in the next step. It consists of a mixture of 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)hexan-1-ol and 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-3-methyl-2-(trifluoromethyl)pentan-1-ol (ratio 30:70).
