{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Reactions \u2192 Product Determination", "refinement": "This problem involves analyzing organic reactions to determine the main products based on steric effects and stability considerations.", "specific_scope": "The focus is on two specific reactions: the reaction of 2-ethyl-2,6-dimethylcyclohexan-1-one with ethyl acrylate in the presence of t-BuOK, and the reaction of 1-nitropropane with KOH and (E)-but-2-enenitrile.", "goal": "Identify the correct structures of the main products (A and B) from the given reaction scenarios."}, "summary": "This problem requires understanding organic chemistry reactions and the factors influencing product formation, such as steric effects and stability. The first reaction involves a cyclohexanone derivative reacting with an acrylate, leading to a specific ester product. The second reaction involves a nitro compound reacting with a base and an alkene to yield a nitrile product. The correct answers for the products are A = ethyl 3-(3-ethyl-1,3-dimethyl-2-oxocyclohexyl)propanoate and B = 3-methyl-4-nitrohexanenitrile, which reflect the expected outcomes based on the reaction conditions."}