[CH2:1]([C:3]1[C:4]([O:21][CH3:22])=[C:5]([CH:9]([CH2:19][CH3:20])[CH2:10][C:11]([C:15]([F:18])([F:17])[F:16])([OH:14])[CH2:12][OH:13])[CH:6]=[CH:7][CH:8]=1)[CH3:2].C(C1C(OC)=C(C(C)C(C)C(C(F)(F)F)(O)CO)C=CC=1)C.C1(O)C=CC=CC=1.[NH4+].[Cl-]>>[CH2:1]([C:3]1[C:4]([O:21][CH3:22])=[C:5]([CH:9]([CH2:19][CH3:20])[CH2:10][C:11]([OH:14])([C:15]([F:16])([F:18])[F:17])[CH:12]=[O:13])[CH:6]=[CH:7][CH:8]=1)[CH3:2]2.28 (7.12 mmol) of a mixture of 4-(3-ethyl-2-methoxyphenyl)-2-(trifluoromethyl)-hexane-1,2-diol and 4-(3-ethyl-2-methoxyphenyl)-3-methyl-2-(trifluoromethyl)-pentane-1,2-diol (prepared in analogy to the sequence described in Example 110: acetylation of the corresponding phenol, Fries displacement of the acetyl group, etherification of the phenol, Wittig reaction, ene reaction, reduction of the ester to the alcohol) are reacted conventionally with SO3/pyridine complex (3.4 g, 21.35 mmol). After three-hour stirring at room temperature the reaction mixture is poured onto a mixture of saturated NH4Cl solution and ice. It is extracted three times with diethyl ether. The combined organic extracts are washed twice with brine and dried (Na2SO4). Following removal of the solvent on a rotary evaporator, the residue is purified by means of chromatography. (silica gel, eluent: hexane/ethyl acetate). This gives 2.07 g (91.4%) of a mixture of the two aldehydes.
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