See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

Step 1 - Identify each radical type: - Radical 1: The dot is on an exocyclic carbon attached to cyclohexane. Looking at the structure carefully, the radical is on a carbon that is part of the cyclohexane ring (secondary radical, no special stabilization beyond being secondary). - Radical 2: The radical is on C1 of cyclohexane with a phenyl (Ph) group also on C1. This is a tertiary radical AND benzylic radical - doubly stabilized (tertiary + benzylic resonance with the phenyl ring). - Radical 3: The radical is on a ring carbon of cyclohexane with no other substituents - a simple secondary radical. - Radical 4: The radical is on C1 of cyclohex-2-ene (allylic position, adjacent to the double bond) - an allylic radical stabilized by resonance. Step 2 - Rank stabilization factors: - Radical 1: secondary radical on a carbon bearing the cyclohexane ring but no conjugation - least stabilized among these (essentially like a simple secondary radical, comparable to or slightly less than plain secondary). - Radical 3: secondary radical on cyclohexane ring - simple secondary radical. - Radical 4: allylic radical - stabilized by resonance delocalization over the double bond, more stable than a simple secondary radical. - Radical 2: tertiary + benzylic radical - most stable due to hyperconjugation/induction (tertiary) plus extensive resonance with the phenyl ring. Step 3 - Order of increasing stability (least to most): Radical 1 (secondary, no resonance) < Radical 3 (secondary, no resonance, but ring carbon) < Radical 4 (allylic, resonance-stabilized) < Radical 2 (tertiary + benzylic, most stabilized). This gives: 1 < 3 < 4 < 2, which corresponds to answer choice (c). Step 4 - Why other options fail: - (a) 4 < 2 < 1 < 3: Places allylic radical as least stable and benzylic/tertiary as second - incorrect. - (b) 3 < 1 < 2 < 4: Places allylic as most stable over benzylic/tertiary - incorrect. - (d) 2 < 4 < 3 < 1: Completely reverses the correct order - incorrect. Therefore, the correct answer is C.