How many stereoisomers (enantiomers and diastereomers) are there of this molecule. Note the possible symmetry of the stereoisomers is a function of the absolute configurations.

Question

TestHub · Accepted Answer

Ans. Total optical isomers = 2^(n-1) + 2^(n/2-1) = 2^(6-1) + 2^(6/2-1) = 32 + 4 = 36 (32 optically active + 4 meso).

Sol. The molecule is symmetrical with n = 6 chiral centres (even n, identical ends): the four CH(CH₃) carbons and the two CH(Cl) carbons are all stereogenic. For a symmetrical compound with an even number of chiral centres: optically active forms = 2^(n-1) = 2⁵ = 32 and meso forms = 2^(n/2-1) = 2² = 4, so the total number of stereoisomers is 36.

Chemistry - STEREO ISOMERISM Question with Solution | TestHub

Doubts & Discussion