The total number of stereoisomers that can exist for M is
← JEE Advanced 2015 · Paper 1![Compound M: camphor (1,7,7-trimethylbicyclo[2.2.1]heptan-2-one), drawn as a bridged bicyclic ketone with a gem-dimethyl bridge and a bridgehead methyl next to the C=O.](/figures/ja-2015-p1/ja-2015-p1-che-q21-f1.png)
ChemistryInteger+4Question 21 of 60
JEE Advanced 2015 · Paper 1, Chemistry question 21
Answer and worked solution
Official answer: 2
Camphor has two stereocentres, the bridgehead carbons C1 and C4. The one-carbon bridge forces both bridges onto the same face, so the two centres cannot be set independently. Only one pair of enantiomers exists: (+)- and (−)-camphor.
Answer: 2