Dimethyl Sulfoxide → 4-(4-Isopropyl-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)hexanal

Participants

Reaction Steps

The above-described 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 (5.35 g, 16 mmol) is dissolved in dichloromethane (164 ml). Following addition of dimethyl sulphoxide (54.8 ml) and triethylamine (11.1 ml) the SO3/pyridine complex (6.37 g, 40 mmol) is added in portions over the course of 40 minutes. After four-hour stirring at room temperature, the batch is poured onto a mixture of saturated NH4Cl solution and ice. The mixture is extracted twice with diethyl ether (250 ml each time) and the combined extracts are washed twice with brine (50 ml each time). Following removal of the solvent by evaporation, the residue is chromatographed on silica gel (eluent: hexane/diethyl ether). This isolates 3.05 g (57%) of a mixture of the two aldehydes, 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-2-(trifluoromethyl)-hexanal and 4-(4-isopropyl-2-methoxyphenyl)-2-hydroxy-3-methyl-2-(trifluoromethyl)pentanal.

Provenance & Evidence