One stereoisomer of 3-hexene forms a meso compound when it reacts with Br2, while the other
stereoisomer forms a racemic mixture of products. Draw both halogenation reactions, clearly
showing starting material and product stereochemistry. Indicate the racemic mixture using （±）

Question

One stereoisomer of 3-hexene forms a meso compound when it reacts with Br2, while the other
stereoisomer forms a racemic mixture of products. Draw both halogenation reactions, clearly
showing starting material and product stereochemistry. Indicate the racemic mixture using （±）

caozeyuan · Answer

@Photon336  got any idea?

photon336 · Answer

my drawing bar froze

photon336 · Answer

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caozeyuan · Answer

How to get the racemate? I know meso is due to symmetry of hexene, but I am not sure how racemate is fromed

photon336 · Answer

racemic mixture means that there are equal amounts  of R:S enantiomers.

caozeyuan · Answer

Oh, that's how you get raceic mixture, of cuz!!!

photon336 · Answer

:) it depends on the mechanism of your reaction too. many SN1 reactions have a carbocation intermediate here take this for example. 

Carbocations are in fact planar. and when we have a reaction like an SN1 type the nucleophile can equally attack the top or bottom face. of the intermediate  which leads to a 50:50 racemic mixture of our enantiomers. 

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