Naming Bicyclic Organic Compounds: Unraveling the Chemistry Behind the Structures
Which is the correct chemical name for the given bicyclic organic compound?
CH3 H Н CH3 H3C
a. 4-isopropyl-2-methylbicyclo[4.3.0]nonane-8-carbaldehyde
b. 6-isopropyl-8-methylbicyclo[4.3.0]nonane-2-carbaldehyde
c. 5-isopropyl-7-methylbicyclo[4.3.0]nonane-1-carbaldehyde
d. 8-isopropyl-6-methylbicyclo[4.3.0]nonane-2-carbaldehyde
Answer:
The correct chemical name for the given bicyclic organic compound is 6-isopropyl-8-methylbicyclo[4.3.0]nonane-2-carbaldehyde.
The name of this compound is systematically derived following the rules of IUPAC nomenclature. The bicyclic structure is indicated by "bicyclo[4.3.0]nonane," representing a nonane backbone with two bridgehead carbons and a transannular double bond between carbon 4 and carbon 7.
The compound bears two substituents: an isopropyl group (CH3CH(CH3)2) and a methyl group (CH3). By assigning the lowest possible numbers to the substituents, we find that the isopropyl group is attached to carbon 6, the methyl group is attached to carbon 8, and the carbaldehyde functional group (H-C=O) is attached to carbon 2.
Putting all these details together, the systematic IUPAC name is 6-isopropyl-8-methylbicyclo[4.3.0]nonane-2-carbaldehyde. This name accurately reflects the compound's structural features, including the arrangement of rings, substituent positions, and the presence of the aldehyde group.
The process of naming complex organic compounds involves careful consideration of the arrangement of atoms and functional groups to provide a clear and unambiguous description of the molecule's structure. The IUPAC nomenclature system ensures that chemists worldwide can communicate effectively about specific compounds, promoting accuracy and consistency in chemical discussions.
Thus, the correct systematic IUPAC name for the given bicyclic compound is 6-isopropyl-8-methylbicyclo[4.3.0]nonane-2-carbaldehyde, accurately representing its unique structural characteristics.
Therefore, option 'b' is the correct answer.