See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the functional group. The structure CH2=C(Me)-C(=O)-OC2H5 contains an ester group (-C(=O)-OC2H5), so the parent name ends in '-oate' and the alcohol portion is 'ethyl'. Step 2: Identify the parent chain. The acid portion is CH2=C(Me)-C(=O)-O-, which contains 3 carbons (propanoate backbone) with a double bond. Step 3: Number the chain. For the acid/ester, the carbonyl carbon is C1. So: C1 is the carbonyl carbon, C2 bears the methyl group, and C3 is the terminal =CH2. Step 4: Locate the double bond. The double bond is between C2 and C3, giving 'prop-2-enoate'. Step 5: Name the substituent. There is a methyl group at C2, giving '2-methyl'. Step 6: Combine. The full name is ethyl 2-methylprop-2-enoate. Why other options fail: - (b) 'prop-1-enoate' would place the double bond between C1 and C2, but C1 is the carbonyl carbon, so a double bond there is not possible in an ester context. - (c) '-enone' implies a ketone carbonyl, but this is an ester, not a ketone. - (d) '-enal' implies an aldehyde, which this is not. Therefore, the correct answer is A.