合成路线1

Synthesis of aldehyde intermediate (IX): The condensation of 1-tert-butoxy-4-chlorobutane (I) with 4-methyl-3-penten-2-one (II) by means of Mg in hot THF gives the 2-octanone (III), which is condensed with hexafluoroacetone (IV) by means of diethyl chlorophosphate and LDA in THF to yield the fluorinated alkynol (V). Hydrogenation of the triple bond of (V) with H2 and Lindlar catalyst affords the cis-alkene (VI), which is deprotected with sulfuric acid to provide the fluorinated diol (VII). Finally, the primary alcohol of (VII) is oxidized to the corresponding aldehyde (VIII) with NaOCl and tempo, which is silylated with Tes-Cl and TEA to afford the desired intermediate (IX).