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چکیده
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The formation of chiral carbon – carbon bonds by using the asymmetric conjugate addition reaction has been widely investigated. Michael addition of organometallics, particularly organocoppers and organozincs, to α,ß-unsaturated carbonyl compounds is a well-established method for this formation. As a part of a broader program aimed at the development of chiral metal complexes for asymmetric synthesis, herein we have focused on synthesis of chiral C2-symmetric 2,2′ bisoxazoline ligands and their application in copper-catalyzed asymmetric 1,4-Addition of Diethylzinc to Enones. on the other hand, Chiral bisoxazolines, which is the most successful ligand in the area of asymmetric catalysis, form superior catalysts with a broad variety of metals such as copper. We found that the cu-catalized asymmetric conjugate addition of dialkylzinc reagentes a viable approach, using chiral C2-symmetric biaryl bisoxazoline ligands. focusing on the cu-catalized asymmetric conjugate 1,4- addition of diethylzinc to enones .we first synthesized chiral 2,2′- bisoxazoline ligands in high yield and enantiomeric excess and then generated Cu(II) complexes 1-2 from Cu(OTf)2 and these ligands (Scheme 1). In general, The effects of temperature, the substitutions at the ligands and chalcones are investigated
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