Chemistry - STEREO ISOMERISM Question with Solution | TestHub

Ans. (C) 2.

Sol. The molecule has four stereocentres (the two ring carbons at 1,4 and the two side-chain methine carbons), with a symmetry exchanging the two halves. Writing the configuration of one half as (a,b), meso forms require the second half to be the mirror image of the first; the two free choices give (R,R,S,S) and (R,S,S,R) after accounting for the molecular symmetry. Meso-isomers = 2.