合成路线1

Synthesis of intermediates: Iodinated pivalate (X): The condensation of 3-iodo-2-methyl-2-propenal (I) with the silylated enol ether (II) by means of Zr(O-tBu)4 and 3,3'-I2-BINOL in toluene gives the iodopentenoic acid (III), which is treated with Tips-Cl and imidazole to yield the silyl ether (IV). The reduction of (IV) by means of DIBAL in dichloromethane affords the 5-iodopenten-1-ol (V), which is oxidized by means of (COCl)2 in DMSO/dichloromethane to provide the aldehyde (VI). The Wittig condensation of (VI) with phosphorane (VII) in refluxing THF leads to the heptadienoic ester (VIII), which is reduced with DIBAL in dichloromethane giving the primary alcohol (IX). Finally this alcohol is esterified pivaloyl chloride and pyridine to affords the target iodinated pivalate (X).