{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Chemistry \u2192 Spectroscopy", "refinement": "This problem involves interpreting NMR spectroscopy data to deduce structural information about organic compounds, specifically focusing on the relationships between different hydrogen environments in a molecule.", "specific_scope": "The context is a reaction involving a dicarboxylic acid anhydride and a cyclopentadiene derivative, leading to products that can be analyzed using 1H and 2D NOESY NMR spectroscopy.", "goal": "Identify the specific hydrogen resonances in the major product that are correlated through NOE effects, indicating spatial proximity in the molecular structure."}, "summary": "This problem requires understanding NMR spectroscopy, particularly 1H and 2D NOESY techniques, to analyze the structural features of organic compounds. The scenario describes a reaction involving a dicarboxylic acid anhydride and a cyclopentadiene, resulting in two products. The goal is to determine which hydrogen resonances in the major product are linked by a cross-peak in the NOESY spectrum, indicating they are spatially close in the molecular structure. The correct answer identifies a 1H doublet at 1.5 ppm and a 2H singlet at 3.5 ppm as the resonances linked by this cross-peak."}