The Diels-Alder reaction is one of the most well-known ring-forming reactions, and commonplace in an undergraduate chemist's education. However, the standard model fails to predict the template leading to the correct set of reactants as shown in Figure , for substrates 7 and 8. The hetero Diels-Alder approach cannot be predicted by either the USPTO or Reaxys models for the synthesis of quinolines (Figure , substrate 8). However, when applied to the substituted cyclohexene (Figure , substrate 7), the 'Ring Breaker' models are able to successfully identify the diene and dienophile used in the literature with a high probability for the USPTO (template rank 1, p=0.951) and Reaxys (template rank 1, p=0.998) 'Ring Breaker' models. In addition, the synthesis of dihydroisoquinolines (Figure , substrate 9) via the Bischler-Napieralski reaction was successfully predicted by both the USPTO (template rank 1, p=0.997) and Reaxys (template rank 1, p=0.976) 'Ring Breaker' models, leading to β-arylethylamide, as reported in the literature (Figure , substrate 9). In the case of both the Diels-Alder and Bischler-Napieralski reaction, the standard model consistently predicts alternate, and feasible strategies leading to the ring containing fragment; this demonstrates the utility of 'Ring Breaker' as a method of focusing the synthetic strategy toward ring formations at a given step. One exception we found to 'Ring Breakers' increased performance over the standard model, is the prediction of the dihydroisoquinoline (Figure , substrate 9) using the USPTO standard model (template rank 1, p=0.966), where the standard model predicts the ring formation with a high probability.