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The axially dissymmetric chiral Schiff base ligand 10, prepared by the reaction of (R)-(+)-1,1′-binaphthyl-2,2′-diamine with (R)-(+)-2,2′-dihydroxy-[1,1′]-binaphthalenyl-3-carbaldehyde, is a fairly effective chiral ligand for the catalytic asymmetric addition reaction of diethylzinc to aldehydes. [Copyright &y& Elsevier]

We utilized a reported quinidine-derived chiral amine 1 to catalyze the asymmetric Baylis–Hillman reaction of aldehydes with methyl vinyl ketone. The enantioselectivities increase and in some cases, the absolute configuration of the Baylis–Hillman adducts can be inverted by the use of proline or lithium salt additives. The highest ee achieved is 49% with S configuration at the newly formed stereogenic centre. When using chiral amine 1 to catalyze the asymmetric Baylis–Hillman reaction of aldehydes with (α)-naphthyl acrylate, ee as high as 92% can be achieved. [Copyright &y& Elsevier]