Biomimetic reductive amination process

Transamination On-column 1,3-proton shift reactions-a key transformation in the biomimetic reductive amination process - were investigated using simple silica-adsorbed l,8-diazabicyclo[5.4.0]undec-7-ene (DBU) catalyst [42, 43]. This process enabled chirality transfer from (H)-l-phenylethylamine to perfluoroalky-lated ketones. The continuous-flow process proved to be far superior to the batch processes, both from an economical and synthetic point of view. 

We call reductive amination a biomimetic ( mimicking the biological process ) synthesis because it resembles the biological synthesis of amino acids. The biosynthesis begins with reductive amination of a-ketoglutaric acid (an intermediate in the... 

In 2005, Huang et al. reported a tandem asymmetric conjugate reduction-fluorina-tion reaction by an efficient combination of iminium and enamine catalysis using two distinct secondary amine catalysts [16]. This method offered direct access to chiral multifunctionalized aldehydes from P-substituted enals and electrophilic florinated reagents in a biomimetic way (Schane 9.13). The diastereoselectivity of the products varied depending on the catalyst combination (Scheme 9.14). The chemistry presented here demonstrated for the first time the power of the multicatalysis process for control of the product diastereoselectivity based on the cycle-specific catalysis concept. 

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