{"knowledge_schema": {"broad_category": "Chemistry \u2192 Organic Chemistry \u2192 Functional Groups and Reactions", "refinement": "This problem involves understanding the concept of index of hydrogen deficiency (IHD) and how it relates to the structure of organic compounds, particularly after a reduction reaction.", "specific_scope": "The focus is on determining the IHD of a specific compound (2-formyl-5-vinylcyclohex-3-enecarboxylic acid) after it undergoes reduction with red phosphorus and excess HI, which typically adds hydrogen to the compound.", "goal": "Calculate the index of hydrogen deficiency for the reduced compound to understand its saturation level."}, "summary": "This problem is rooted in organic chemistry, specifically in calculating the index of hydrogen deficiency (IHD) for a compound after a reduction reaction. The compound in question is 2-formyl-5-vinylcyclohex-3-enecarboxylic acid, which undergoes reduction with red phosphorus and excess HI. The goal is to determine the IHD of the resulting compound, which indicates the degree of unsaturation. The answer is 1, suggesting that the reduced compound has one degree of unsaturation."}