| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1348152 | Tetrahedron: Asymmetry | 2006 | 6 Pages |
Chiral dinuclear titanium(IV) complexes (generated in situ from hexadentate Schiff bases and titanium tetra-isopropoxide) have been found to be more effective catalysts for the asymmetric addition of trimethylsilyl cyanide to aldehydes and the ring opening of cyclohexene oxide than their mononuclear analogues. The best results were obtained for benzaldehyde (86% enantiomeric excess) and cyclohexene oxide (89% enantiomeric excess).
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3,3′-[((S)-1-Hydroxymethyl-2-methylpropyl)imino]methyl-2,2′-dihydroxy-1,1′-biphenylC24H32N2O4Ee = 100%[α]D25=-143.8 (c 1, MeOH)Source of chirality: synthesis from (S)-valineAbsolute configuration: (S,S)
3,3′-[((S)-1-Hydroxymethyl-2-methylpropyl)imino]methyl-2,2′-dihydroxy-(R)-1,1′-binaphthaleneC32H36N2O4Ee = 100%[α]D25=-139.8 (c 1, CHCl3)Source of chirality: synthesis from (S)-valine and (R)-binolAbsolute configuration: (S,S,aR)
3,3′-[((S)-1-Hydroxymethyl-2-methylpropyl)imino]methyl-2,2′-dihydroxy-(S)-1,1′-binaphthaleneC32H36N2O4Ee = 100%[α]D25=-163 (c 1, CHCl3)Source of chirality: synthesis from (S)-valine and (S)-binolAbsolute configuration: (S,S,aS)
N-(2-Hydroxy-3,5-di-tert-butyl-benzylidene)-(S)-2-amino-3-methylbutan-1-olC20H33NO2Ee = 96.6%[α]D25=-33.3 (c 0.78, MeOH)Source of chirality: synthesis from (S)-valineAbsolute configuration: (S)
N-(2-Hydroxybenzylidene)-(S)-2-amino-3-methylbutan-1-olC12H17NO2Ee = 96.6%[α]D25=-25.0 (c 0.8, MeOH)Source of chirality: synthesis from (S)-valineAbsolute configuration: (S)
