Chiral poisoning, asymmetric amplification

Related concepts asymmetric amplification chiral poisoning asymmetric activation... 

VII. Asymmetric amplification in chiral poisoning or chiral activation of a racemic catalyst... 

VII. ASYMMETRIC AMPLIFICATION IN CHIRAL POISONING OR CHIRAL ACTIVATION OF A RACEMIC CATALYST... 

Faller, J. W., Sams, D. W. I., Liu, X. Catalytic Asymmetric Synthesis of Homoallylic Alcohols Chiral Amplification and Chiral Poisoning in a Titanium/BINOL Catalyst System. J. Am. Chem. Soc. 1996,118, 1217-1218. 

The reaction of methallyltri-n-butylstannane 117 with achiral aldehydes is also effectively promoted by the binol-Ti complex [89 c]. In all but one case (cyclo-hexanecarboxaldehyde), the yields and enantioselectivities observed with the methallylstannane are identical or higher than those obtained in the reactions with allyltributylstannane with only 10 mol% of the binol-Ti complex (Scheme 10-50). Insight into the nature of the titanium catalyst is provided by the observation of asymmetric amplification [89 b] and chiral poisoning [89 g]. An intruiging hypothesis on the origin of enantioselection in allylation and related reactions [89 h]. 

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