In this study, we utilised the USPTO dataset pre-processed by Pesciullesi et al., which is henceforth referred to as the General dataset. Additionally, we curated a dataset of 165,216 ring formation reactions, referred here to as the Ring dataset, comprising about 80k reactions extracted from academic journals (CJHIF dataset ) and 80k reactions from additional patent data (Pistachio dataset). The creation of the Ring dataset is described in more detail in SI §S4. A visualisation of the chemical space of the datasets is included in the SI (Figure ), showing that ring-breaking reactions occupy distinct areas of the chemical space.