To avoid a resource-prohibitive scenario resulting from the full factorial combination of all substrates, which would warrant the development of 288 quantitative assays, we coupled aryl-bromides and primary amines from various clusters within their chemical spaces to initially obtain 37 distinct products (further details available in the SI). All assayed products underwent two distinct control experiments that included a ligand-free condition where no ligand was introduced and a reaction without any ligand or copper source. These measures were essential to ascertain that the observed variances in reactivity were attributed to catalysis rather than SNAr or other side reactions . Nine of the unique products (P001-P009) failed the control tests and, therefore, were removed from the training dataset (see details in the SI). For the reactions that showed evidence of catalysis, we set a threshold of two catalytic turnovers (20% yield) to discern reactivity as either "on" or "off". The choice of two catalytic turnovers was grounded in practical relevance within the realms of reaction/drug development protocols-two catalytic turnovers could provide sufficient material in drug/library synthesis campaigns, while also being a plausible lead to initiate optimization campaigns in process chemistry .