Answer to Question #125246 in Organic Chemistry for Shukri

Question

The following compound has only one asymmetric center. Why then does it have four stereoisomers? Explain your answer by drawing hem.CH 3 CH 2 CH(Br)CH 2 CH=CHCH 3

Answer 1

Number of stereoisomers are not only depends on asymmetric centre only but also depends on geometrical stereocentre.

So this structure have two stereocentre unit one optical asymmetric stereo centre unit and other is geometrical stereocentre unit.

No. Of stereoisomers formula = 2ⁿ Where n is no. of stereocentre unit.

So in above question there is two stereocentre unit so no. of total stereoisomers = 2²

= 4 stereoisomers

CH₃ - CH₂ - CH(Br) - CH₂ - CH=CH - CH₃

Asymmetric Geometrical Stereocentre Stereocentre

Unit unit