MolSynapsequestion bank
MolSynapse / Question bank / Haloalkanes and Haloarenes / SN2 stereochemistry on drawn chiral halides
JEE Main levelOne or more correct optionsDifficulty 2 of 3hx233

The optically active bromide shown is dissolved in dry acetone containing a large excess of . Each bromide exchange occurs by SN2. Select all correct statements.

  1. AEach exchange inverts the configuration of the stereocentre.
  2. BThe optical rotation of the solution gradually falls towards zero.
  3. CThe constitution of the haloalkane does not change during the process.
  4. DThe solution keeps its original optical rotation because bromide replaces bromide.

Answer: A, B, C

Every Br-for-Br exchange is an SN2 displacement that inverts the carbon. Repeated exchange interconverts the two enantiomers until a 1:1 mixture remains, so optical rotation falls to zero although the constitution of the compound never changes. Optical activity is therefore not retained.
Practice Haloalkanes and Haloarenes More on SN2 stereochemistry on drawn chiral halides
Previous questionNext question

More questions on SN2 stereochemistry on drawn chiral halides