TY - JOUR T1 - Direct asymmetric Michael reactions of cyclic 1,3-dicarbonyl compounds and enamines catalyzed by chiral bisoxazoline-copper(II) complexes. AU - Halland,Nis, AU - Velgaard,Thomas, AU - Jørgensen,Karl Anker, PY - 2003/6/21/pubmed PY - 2003/6/21/medline PY - 2003/6/21/entrez SP - 5067 EP - 74 JF - The Journal of organic chemistry JO - J Org Chem VL - 68 IS - 13 N2 - The catalytic direct Michael addition of cyclic 1,3-dicarbonyl compounds and enamines to unsaturated 2-ketoesters is presented. A series of different 4-hydroxycoumarins, 4-hydroxy-6-methyl-2-pyrone, 3-hydroxy-1H-phenalene-1-one, 2-hydroxy-1,4-naphthoquinone, 5,5-dimethyl-1,3-cyclohexanedione, and various enamines of cyclic 1,3-diketones all add to unsaturated 4-substituted 2-ketoesters in an enantioselective manner. The reaction is catalyzed by chiral bisoxazoline-copper(II) complexes and proceeds in the absence of base to afford Michael adducts in good to high yields and with up to 98% ee. The products formed are substructures found in skeletons of important biological and pharmaceutical molecules. The scope and potential of the new reaction are discussed as well as the mechanism for the catalytic enantioselective reaction. SN - 0022-3263 UR - https://www.unboundmedicine.com/medline/citation/12816459/Direct_asymmetric_Michael_reactions_of_cyclic_13_dicarbonyl_compounds_and_enamines_catalyzed_by_chiral_bisoxazoline_copper_II__complexes_ DB - PRIME DP - Unbound Medicine ER -