Asymmetric Cyclization via Tandem Conjugate Addition by Using Metal Amide Reagents. Importance of the Folded Orientation of Two Enoate Moieties

Article abstract of DOI:10.1021/jo00045a003

Di-(-)-menthyl nona-2,7-diene-1,9-dioate (1) is converted to (-)-menthyl 3(S)-(N-benzylamino)-2(S)-(-)-menthoxycarbonyl-1(S)-cyclohexane-1-acetate (2) with high diastereoselectivity upon treatment with the amide cuprate or zincate reagent Bn(TMS)NML_n in the presence of ZnCl2.The folded orientation of the two enoate moieties of 1 is essential for this high asymmetric cyclization via tandem conjugate addition.