176244-01-2Relevant articles and documents
Enantioface-differentiating protonation with chiral γ-hydroxyselenoxides
Takahashi, Tamiko,Nakao, Naoki,Koizumi, Toru
, p. 3293 - 3308 (2007/10/03)
Enantioface-differentiating protonation of a chiral metal enolates of α-alkylcarbonyl compounds 7 has been developed using chiral γ-hydroxyselenoxides 1 as a proton source. Reaction of zinc bromide enolates of 2-benzyl- and 2-n-propylcyclohexanones with (S(Se))-1e gave (S)-2-benzylcyclohexanone 7a and (R)-2-n-propylcyclohexanone 7c in high enantiomeric excess, respectively. Intramolecular hydrogen bonding of the selenoxide 1, chelation effects between 1 and metal enolate, and 2-exo-hydroxy-10-bornyl-framework could contribute to this asymmetric induction.
The first example of enantioselective protonation of prochiral enolates with chiral γ-hydroxyselenoxides
Takahashi, Tamiko,Nakao, Naoki,Koizumi, Toru
, p. 207 - 208 (2007/10/03)
Enantioselective protonation of a simple enolate has been developed using an optically pure γ-hydroxyselenoxide 1 as a chiral proton source. Reaction of zinc bromide enolate 7b with (Sse)-selenoxide (Sse)-1c gave (S)-2-benzylcyclohexanone (S)-8 with high enantioselectivity. Intramolecular hydrogen bonding between hydroxy group and seleninyl-oxygen of 1 would contribute to this asymmetric induction.