Formal Enantioselective Hydroamination of Non‐Activated Alkenes: Transformation of Styrenes into Enantiomerically Pure 1‐Phenylethylamines in Chemoenzymatic One‐Pot Synthesis

As a complementary approach to current asymmetric synthetic methods, a direct transformation of styrenes into 1‐phenylethylamines was developed. The one‐pot process represents a formal hydroamination of a non‐activated alkene with ammonia and is based on the combination of a Pd/Cu‐catalyzed Wacker‐oxidation with an enzymatic transamination. A key feature of this process is the compartmentation of the catalytic systems, which turned out to be essential to avoid deactivation of the transaminase by the Cu‐component. This one‐pot synthesis can be applied to a broad substrate range, which leads to the chiral amines with high conversions and excellent enantioselectivities of >99 % ee. As a complementary approach to current asymmetric amine synthetic methods, a direct conversion of styrenes to 1‐phenylethyl‐amines was developed, which represents a formal hydro‐amination with ammonia. The one‐pot process is based on a combination of a Pd/Cu‐catalyzed Wacker‐oxidation with an enzymatic transamination under compartmentation of the catalytic systems.