A Mechanistic Insight into a Simple C−N Bond Formation via SN2 Displacement: A Synergistic Kinetics and Design of Experiment Approach

A novel series of 1,2,4-triazol-3-yl-azabicyclo[3.1.0]hexanes was recently identified as new highly potent and selective dopamine (DA) D3 receptor antagonists. This class of molecules deserved the Chemical Development special attention to quantify the reliability and robustness of the pivotal SN2 displacement step between the 1,2,4-triazol-3-yl-halide derivative (4) and variously substituted azabicyclo[3.1.0]hexanes (5). To reach this goal we applied the classical Design of Experiment (DoE) approach, simultaneously trying to build up a descriptive kinetic model of the chemistry. The synergistic use of these two techniques allowed us to select new, higher-yielding and more robust reaction conditions and, at the same time, to identify their Design Space.