{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Chemistry \u2192 Reaction Mechanisms", "refinement": "This problem involves understanding the reactions of carbonyl compounds and nucleophilic additions, as well as the effects of steric hindrance and product stability.", "specific_scope": "The focus is on two specific reactions: the reaction of a ketone with an acrylate and the reaction of a nitro compound with a nitrile, both under specific conditions.", "goal": "Identify the major products of the given reactions based on steric and stability considerations."}, "summary": "This problem requires knowledge of organic chemistry, specifically the mechanisms of reactions involving carbonyl compounds and nucleophiles. The first reaction involves a ketone reacting with ethyl acrylate in the presence of a strong base, leading to the formation of a product that considers steric hindrance and stability. The second reaction involves a nitro compound reacting with a nitrile, where the major product is determined by similar considerations. The correct answers are A = ethyl 3-(3-ethyl-1,3-dimethyl-2-oxocyclohexyl)propanoate and B = 3-methyl-4-nitrohexanenitrile."}