合成路线1

The reaction of cyclohexane-1,3,5-triol (I) with trimethyl orthobenzoate (II) by means of BF3/Et2O gives the cyclic orthoester (III), which is partially reduced with borane in THF to yield the alcohol (IV). Oxidation with Dess-Martin periodinane affords cyclohexanone (V), which is enantioselectively deprotonated with the chiral lithium (S,S')-alpha,alpha'-dimethyldibenzylamide (VI) in the presence of Tms-Cl in THF to provide the chiral silylated enol ether (VII). Ozonolysis of the double bond of (VII) gives the 6-oxohexanoic acid (VIII), which is reduced with NaBH4 to the corresponding hydroxyacid (IX). The methylation of (IX) with methyl iodide and K2CO3 yields the hydroxyester (X), which is oxidized with oxalyl chloride in DMSO to afford the oxoester (XI). The Wittig condensation of (XI) with decyltriphenylphosphonium bromide (XII) by means of BuLi in THF provides the unsaturated hexadecenoic ester (XIII), which is finally reduced, deprotected and cyclized by treatment with H2 over Pd/C in acetic acid to furnish the target (4S,6S)-4-hydroxy-6-undecyltetrahydrofuran-2-one (XIV). The conversion of (XIV) into tetrahydrolipstatin has already been described in scheme 11082304a.