Chemo‐Enzymatic Cascade Reactions for the Synthesis of Chiral Intermediates and Nonaromatic Nitrogen Heterocycles

Chiral amines are prevalent in active pharmaceutical ingredients, agrochemicals, and bioactive natural products and are important pharmaceutical building blocks. However, efficient methods for their preparation are limited. As such, the development of broadly applicable (bio)catalytic or chemoenzymatic strategies for their synthesis is of great interest, and the possibility of process optimization in an economical and environmental approach is very plausible. The cellular metabolism requires a wide range of enzymatic transformations in multi-step one-pot reactions to synthesize infinity of products with high selectivity. In traditional organic synthesis, sequential intermediates are produced and isolated, often purified before proceeding to the next synthetic step. In the last decade, many successful efforts have been made to combine chemo- and (bio)catalysts in cascade reactions. The concept of chemoenzymatic cascade reactions have been exploited in the development of methods for the obtaining of nonaromatic nitrogen heterocycles, particularly those bearing one or more chirality centers.