I thought Inositol was clearly chiral since it has 6 asymmetric C atoms. But friends of me argue that it is achiral and i've found websites say the same (http://bip.cnrs-mrs.fr/bip10/Inositol-EJB.pdf). So what am I missing? Is it chiral or achiral?
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2$\begingroup$ Suppose all atoms have the same configuration. Then each atom has two identical substituents; then how are they asymmetric? $\endgroup$ – Ivan Neretin Dec 5 '17 at 9:12
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$\begingroup$ Look here for the chirality of the inositols: ursula.chem.yale.edu/~chem220/chem220js/STUDYAIDS/isomers/… $\endgroup$ – user55119 Feb 24 at 23:27
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Having asymmetric carbon atoms does not in itself make a compound chiral.
A compound is chiral if and only if it is not super(im)posable on its mirror image.
If there's a plane of symmetry, then reflecting in that plane gives the same thing, by definition, and that meets the criterion for super(im)posability - the mirror image is superimposable on the original and therefore the molecule is not chiral.
Only D- and L- chiro-inositol are chiral - all the other stereoisomers have planes of symmetry and are therefore not chiral.
