Abstract
Chiral bisphosphazides complexed with lithium salts efficiently catalyze the direct enantioselective 1,4-addition of dialkyl malonates to acyclic enones. Spectroscopic studies on the stoichiometry of the bisphosphazide and lithium salt have indicated the formation of a 1:1 species as the active enantioselective catalyst. It is suggested that the catalyst generates a complex of the protonated phosphazide and the chiral nucleophile as the key intermediate. The phosphazide moiety appears to be a promising dual basic functionality for stereo- and chemoselective catalytic transformations.
Original language | English |
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Pages (from-to) | 5267-5274 |
Number of pages | 8 |
Journal | Chemistry - A European Journal |
Volume | 14 |
Issue number | 17 |
DOIs | |
Publication status | Published - 2008 Jun 9 |
Keywords
- Asymmetric catalysis
- Basicity
- Lithium
- Michael addition
- Phosphazene base
ASJC Scopus subject areas
- Catalysis
- Organic Chemistry