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Synlett 2005(6): 1024-1026
DOI: 10.1055/s-2005-864816
DOI: 10.1055/s-2005-864816
LETTER
© Georg Thieme Verlag Stuttgart · New YorkMannich-Type Reaction Promoted by an Ionic Liquid
Further Information
Received
25 January 2005
Publication Date:
23 March 2005 (online)
Publication History
Publication Date:
23 March 2005 (online)

Abstract
The Mannich-type reaction of silyl enolates with aldimines occurred smoothly with [emim]OTf as a solvent and without the addition of an activator to afford β-amino carbonyl compounds in excellent yields.
Key words
ionic liquids - Mannich reaction - imine - catalysis
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References
We have already reported that a catalytic amount of Brønsted acid promoted the Mannich-type reaction. [3]
14The Mannich-type reaction of 1a and 2a did not proceed in conventional organic solvents such as Et2O, CH2Cl2, CH3CN, CH3OH, or toluene.
15Due to the fact that [emim]OTf does not dissolve in EtOAc-hexane (4:1), recycling of the ionic liquid is easier than for [bmim]OTf.