Convenient Chemoenzymatic Route to Optically Active β-Aryl-δ-iodo-γ- lactones and β-Aryl-γ-iodo-δ-lactones with the Defined Configurations of Stereogenic Centers

Two δ-iodo-γ-lactones and two γ-iodo-δ-lactones substituted at the β-position with phenyl or 4-methylphenyl ring have been synthesized in both enantiomeric forms. The starting materials were enantiomerically enriched allyl alcohols with an (E)-4-phenylbut-3-en-2-ol system (ee in the range 88– 99%), which were obtained by lipase-catalyzed transesterification. Alcohols were subjected to orthoacetate modification of the Claisen rearrangement. The high stereoselectivity of this reaction led to retention of (E)-configuration of the double bond and complete transfer of chirality from the allyl alcohol to the benzylic position C-3. As a result, chiral γ,δunsaturated esters with retained configuration of the