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Updated: Jul 6, 2026

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes
Published on: August 5, 2016
Dynamic kinetic asymmetric allylic alkylations of allenes
Barry M Trost1, Daniel R Fandrick, Diana C Dinh
1Department of Chemistry, Stanford University, Stanford, CA 94305-5080, USA. bmtrost@stanford.edu
Abstract:
The dynamic kinetic asymmetric allylic alkylations of racemic allene acetates has been developed with the DACH-phenyl Trost ligand 2 to give general access to allenes with high enantiomeric excess (84-95%) for both malonate and amine nucleophiles. Further, a most unusual dependence of enantioselectivity on base has been uncovered. The magnitude of the enantioselectivity is heavily dependent on the base for the malonate nucleophiles, but the sense and magnitude of the asymmetric induction is dependent on the base for the amine nucleophiles. A Rh(I)-catalyzed intramolecular [4 + 2] cycloaddition of the DYKAT products was accomplished to afford formal Diels-Alder adducts, wherein the axial chirality is faithfully transferred into multiple stereogenic centers as well as olefin geometry.
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