Chemistry is the experimental and theoretical study of materials on their properties at both the macroscopic and microscopic levels.In a patent， category: catalyst-ligand, Which mentioned a new discovery about 18531-94-7
Direct asymmetric reductive amination for the synthesis of (S)-rivastigmine
In this article we demonstrate how asymmetric total synthesis of (S)-rivastigmine has been achieved using direct asymmetric reductive amination as the key transformation in four steps. The route started with readily available and cheap m-hydroxyacetophenone, through esterification, asymmetric reductive amination, N-diphenylmethyl deprotection and reductive amination, to provide the final (S)-rivastigmine in 82% overall yield and 96% enantioselectivity. In the asymmetric reductive amination, catalysed by the iridium?phosphoramidite ligand complex and helped by some additives, the readily prepared 3-acetylphenyl ethyl(methyl)carbamate directly reductively coupled with diphenylmethanamine to yield the chiral amine product in 96% ee and 93% yield.
Because enzymes can increase reaction rates by enormous factors and tend to be very specific, category: catalyst-ligand, typically producing only a single product in quantitative yield, they are the focus of active research.you can also check out more blogs about 18531-94-7
Reference：
Metal catalyst and ligand design,
Ligand Template Strategies for Catalyst Encapsulation – NCBI