Catalytic Racemisation of Chiral Amines and Application in Dynamic Kinetic Resolution

A. John Blacker, Matthew J. Stirling, Michael I. Page

Research output: Contribution to journalArticle

87 Citations (Scopus)

Abstract

A mild and efficient procedure for the racemisation of optically active amines has been developed and applied to the dynamic kinetic resolution (DKR) of a racemic amine. Pentamethylcyclopentadienyliridium (III) iodide dimer dissolved in a convenient solvent is the precatalyst that reacts in situ with primary, secondary, or tertiary amines to form what we have named a SCRAM catalyst. This is able to dehydrogenate a substrate amine to form an imine, which, depending upon the reaction conditions, is then reduced back to the amine. When an optically active amine is mixed with the iridium precatalyst, racemisation is observed. The SCRAM catalyst is used under mild conditions compatible with suitable enzymes and acyl donors, and thus the DKR of an amine has been effected, giving significantly higher yield than if the enzyme alone was used. A mixed carbonate was identified as the optimal acyl donor, giving a carbamate product that is readily removed by acidic hydrolysis.

Original languageEnglish
Pages (from-to)642-648
Number of pages7
JournalOrganic Process Research and Development
Volume11
Issue number3
DOIs
Publication statusPublished - 4 May 2007

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Amines
amines
Kinetics
kinetics
SCRAM
enzymes
catalysts
Iridium
Catalysts
Imines
Carbamates
Carbonates
Iodides
Enzymes
iridium
Dimers
iodides
imines
hydrolysis
Hydrolysis

Cite this

Blacker, A. John ; Stirling, Matthew J. ; Page, Michael I. / Catalytic Racemisation of Chiral Amines and Application in Dynamic Kinetic Resolution. In: Organic Process Research and Development. 2007 ; Vol. 11, No. 3. pp. 642-648.
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Catalytic Racemisation of Chiral Amines and Application in Dynamic Kinetic Resolution. / Blacker, A. John; Stirling, Matthew J.; Page, Michael I.

In: Organic Process Research and Development, Vol. 11, No. 3, 04.05.2007, p. 642-648.

Research output: Contribution to journalArticle

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