Ammonium Chloride → (3-{(1R,2S,3R)-3-(tert-Butyldimethylsilanyloxy)-2-[(S)-(E)-3-(tert-butyldimethylsilanoxy)oct-1-enyl]-5-oxocyclopentylsulfanyl} propylsulfanyl)acetic acid methyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

tert-Butyllithium (1.47 mL of a 1.7M solution in pentane, 2.5 mmol) was added dropwise to a solution of tert-butyl[(S)-1-((E)-2-iodovinyl)hexyloxy]dimethylsilane 6 (462.5 mg, 1.25 mmol) in Et2O (6.0 mL) at −78° C. After stirring for 30 min lithium 2-thienylcyanocuprate (6.0 mL of a 0.25M solution in THF, 1.5 mmol) was added and the reaction was stirred an additional 30 min at −78° C. A solution of enone 5 (430 mg, 1.1 mmol) in Et2O (1 mL) was added and stirring was continued for an additional 1 h. The reaction mixture was then quickly poured into saturated aqueous NH4Cl cooled to 0° C. The mixture was extracted with EtOAc and the organic portion was washed with brine, dried (Na2SO4), filtered and concentrated in vacuo. The residue was quickly purified by flash column chromatography (silica gel, 100% hexane followed by 8:1 hex/EtOAc) to afford 270 mg (39%) of the above titled compound.

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