The conjugate addition of organolithium reagents to polyunsaturated conjugate amides containing (S,S)-(+)-pseudoephedrine as chiral auxiliary has been studied in detail. The reaction proceeded with good 1,4-selectivity and excellent stereoselectivity, affording the corresponding addition products with good yields and as highly diastereoenriched isomers. Removal of the chiral auxiliary by reduction or hydrolysis has allowed the preparation of polyfunctionalized chiral building blocks incorporating an alkene moiety suitable for further transformations.
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