Chemistry - STEREO ISOMERISM Question with Solution | TestHub

Calculate $x$ (Resolvable stereoisomers): The molecule is unsymmetrical and contains 3 stereogenic units: a chiral biphenyl axis (atropisomerism), a geometrical double bond ($-CH=CH-$), and a chiral carbon center ($-CH(OH)-$). Thus, the total number of stereoisomers is $2^3=8$, all of which are chiral and resolvable ($x=8$).

Calculate $y$ ($\pi$ electrons in resonance): The conjugated system consists of two benzene rings ($6\times 2=12e^{-}$), one conjugated alkene double bond ($2e^{-}$), and one lone pair from the chlorine atom participating in resonance ($2e^{-}$), giving $y=12+2+2=16$.

Therefore, $(x+y)=8+16=24$.