The correct IUPAC name of the following compound is :
(A)4-methyl-2-nitro-5-oxohept-3-enal
(B)4-methyl-5-oxo-2-nitrohept-3-enal
(C)4-methyl-6-nitro-3-oxohept-4-enal✓ Correct
(D)6-formyl-4-methyl-2-nitrohex-3-enal
Answer: (C)
Solution
The compound contains an aldehyde group (–CHO) which must be at C-1, making it the principal functional group. Numbering from the aldehyde end: C-1 is –CHO, C-2 has a keto group (=O), C-3 is a quaternary carbon with a methyl substituent at C-4, and C-6 bears the nitro group. The double bond is between C-4 and C-5. Following IUPAC rules for priority (aldehyde > ketone > nitro), the correct name is 4-methyl-6-nitro-3-oxohept-4-enal.
JEE Main · 2022 · 28 Jun 2022 · Shift 2 · Single correct option