See image — Haloalkanes and Haloarenes Chemistry Question

💡 Solution & Explanation

Step 1 - Identify the reaction type: The starting material is a quaternary ammonium hydroxide (Hofmann elimination conditions). Heating a quaternary ammonium hydroxide causes E2-type elimination (Hofmann elimination) where the hydroxide acts as base and the trimethylamine is the leaving group. Step 2 - Identify the starting material: The compound is 1-(trimethylammonio)-1-methylcyclopentane hydroxide. The quaternary nitrogen and the methyl group are both on C1 of the cyclopentane ring. There are two types of beta-hydrogens available for elimination: (a) Beta-hydrogens on the ring carbons (C2 of the ring), which would give an endocyclic alkene: 1-methylcyclopent-1-ene (double bond inside the ring with the methyl substituent). (b) Beta-hydrogens on the exocyclic methyl group (CH3 attached to C1), which would give an exocyclic alkene: methylenecyclopentane (cyclopentane=CH2). Step 3 - Apply Hofmann's rule: Hofmann elimination favors removal of the beta-hydrogen from the less substituted carbon (less hindered), giving the less substituted (less Zaitsev) alkene as the major product. The exocyclic methyl group has 3 equivalent beta-hydrogens and leads to methylenecyclopentane (less substituted, terminal alkene). The ring CH2 groups lead to 1-methylcyclopent-1-ene (more substituted, trisubstituted alkene). Step 4 - Assign major and minor products: Under Hofmann conditions, methylenecyclopentane (exocyclic, less substituted) is the major product X (91%) and 1-methylcyclopent-1-ene (endocyclic, more substituted) is the minor product Y (9%). Step 5 - Match to options: Option (c) shows X = methylenecyclopentane (cyclopentane=CH2) as the major product and Y = 1-methylcyclopent-1-ene (cyclopentene with -CH3) as the minor product. This matches perfectly. Why other options fail: - (a) reverses the structures and shows incorrect connectivity - (b) shows two endocyclic alkene isomers, missing the exocyclic product as major - (d) assigns the endocyclic alkene as major (91%) which contradicts Hofmann's rule Therefore, the correct answer is C.