ABSTRACT
References .......................................................................................................................... 754
Nonracemic chiral amines are an important, but not easily prepared, class of organic
molecules. In addition to their value as building blocks for the preparation of pharmaceutical
and agrochemical end products (Figure 31.1) [1], they are increasingly used as ligands for
asymmetric catalysis [2] and resolving agents for crystallization. As with the manufacture on
scale of many fine chemicals, the current trend is to develop catalytic processes for their
production, thereby eliminating the need for the stoichiometric use of reagents that is both
expensive and environmentally unattractive. Both chemo-and biocatalytic approaches to the
preparation of nonracemic chiral amines are currently being explored, with the former relying
to a large extent upon technologies based on the asymmetric hydrogenation of imines [3,4]. In
terms of biocatalysis there are essentially three distinct routes by which optically active amines
can be prepared: (i) kinetic resolutions of the corresponding racemates, including dynamic
kinetic resolution processes; (ii) asymmetric transamination of ketone precursors; and (iii)
deracemization reactions. The aim of this chapter is to highlight the various approaches that
are being investigated and provide some examples of different routes by which optically
active amines can be prepared. The application of some of these routes for the preparation
of chiral amines at industrial scale is also discussed with relevant examples [5].
