反应详情

Analogously to Example 7, 4.84 g of 4-(2-methoxy-4-methylphenyl)-4-methyl-2-oxopentanoic acid ethyl ester is reacted with 7 ml of trifluoromethyltrimethylsilane and 3 ml of tetrabutylammonium fluoride solution (1 M in THF) in 56 ml THF to form 4.14 g of 4-(2-methoxy-4-methylphenyl)-2-hydroxy-4-methyl-2-(trifluoromethyl)pentanoic acid ethyl ester. The product is reduced with 856 mg of lithium aluminum hydride in 170 ml of diethyl ether to 3.58 g of 4-(2-methoxy-4-methylphenyl)-2-hydroxy-4-methyl-2-(trifluoromethyl)pentanol. The oxidation of the diol is carried out analogously to Example 7 under Swern conditions with 1.1 ml of oxalyl chloride, 2.1 ml of DMSO and 8.0 ml of triethylamine to 3.01 g of the title compound.