An , -unsaturated ketone, 3-ethyl-4-methylhex-3-en-2-one, is formed as one of the products when a mixture of two carbonyl compounds is heated with dilute NaOH . Which of the following pairs of reactants can undergo cross-aldol condensation to yield this product?

Step-by-step solution

The given product is an , -unsaturated ketone formed by aldol condensation. To find the reactant carbonyl compounds, we perform a retro-aldol analysis by cleaving the C=C double bond. The structure of 3-ethyl-4-methylhex-3-en-2-one is: CH ₃- C (= O )- C ( CH ₂ CH ₃)= C ( CH ₃)- CH ₂ CH ₃ Cleaving the double bond between C3 and C4: - Add two hydrogen atoms to the -carbon (C3) to get the enolate precursor: CH ₃- C (= O )- CH ₂- CH ₂ CH ₃ (Pentan-2-one). - Add an oxygen atom with a double bond to the -carbon (C4) to g