Efficient cu-catalyzed asymmetric conjugate additions of alkylzincs to trisubstituted cyclic enones.
The first examples of efficient catalytic asymmetric conjugate addition (ACA) of alkylzincs to trisubstituted cyclic enones is disclosed. These Cu-catalyzed reactions proceed efficiently with five- and seven-membered ring substrates to afford the desired products in >/=95% ee. Intermediate enolates can be trapped with alkyl halides to generate a quaternary stereogenic center. The requisite chiral ligand is prepared from commercially available materials and can be used in situ without further purification in the presence of commercial grade (CuOTf)2.PhMe.
Degrado
Sylvia J
SJ
Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA.
Mizutani
Hirotake
H
Hoveyda
Amir H
AH
D000596:Amino Acids / Q000737:chemistry; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D004151:Dipeptides / Q000737:chemistry; D006844:Hydrocarbons, Cyclic / Q000138:chemical synthesis*; D007659:Ketones / Q000138:chemical synthesis*; D009942:Organometallic Compounds / Q000737:chemistry*
D000596:Amino Acids; D004151:Dipeptides; D006844:Hydrocarbons, Cyclic; D007659:Ketones; D009942:Organometallic Compounds; D003300:Copper; C454811:diethylzinc