I don't understand why this molecule is achiral:

achiral molecule

I've circled what I think is the sole chiral center in red. I thought that any molecule with exactly one chiral center is chiral without exception. I built the molecule and its mirror image with my kit and can't find any superimposability.

  • 1
    $\begingroup$ I think it is achiral because one and the same group is attached to the circled carbon center. Yes the substitution is different but it is too far away. The problem with big molecules like these is mirror image criteria becomes difficult because these bulky substituents can have plenty of conformations by rotation. You can only "guess" the chirality of one conformation. $\endgroup$
    – M. Farooq
    Dec 15 '19 at 19:41
  • 4
    $\begingroup$ This could be a case of cryptochirality, but it still is chiral. See this relevant question. $\endgroup$ Dec 15 '19 at 19:51
  • 6
    $\begingroup$ It is chiral. $~$ $\endgroup$
    – orthocresol
    Dec 15 '19 at 20:05
  • $\begingroup$ Thank you. I probably should have guessed since my professor makes mistakes like this a lot. My apologies for posting. $\endgroup$
    – omzrs
    Dec 15 '19 at 20:17
  • 2
    $\begingroup$ @orthocresol: I agree with you, this is a chiral molecule. Unless p-bromobromophenyl group is meant to be a bromo-group. I think OP's teacher made a drawing mistake, if he/she still thinks it's achiral molecule. $\endgroup$ Dec 15 '19 at 20:22

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