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Reactions of cyclohexene's

Right got to hand this in tomorrow but I seem to be clueless can someone explain how to do this?
like the teacher is so ****ing **** I haven't got a clue what to do.
Thanks in advance
Original post by Super199
Right got to hand this in tomorrow but I seem to be clueless can someone explain how to do this?
like the teacher is so ****ing **** I haven't got a clue what to do.
Thanks in advance


It is an electrophilic addition reaction so the product is c6H10Br2, so 1,2- dibromohexane


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Original post by Super199
Right got to hand this in tomorrow but I seem to be clueless can someone explain how to do this?
like the teacher is so ****ing **** I haven't got a clue what to do.
Thanks in advance


Cyclohexene is a cycloalkene. Alkenes undergo electrophilic addition with Br2 forming two C-Br bonds where the alkene pi bond was. The mechanism is the same as any old electrophilic addition, you may have learnt it with a simple alkene such as ethene, the same principal applies here.
Reply 3
Original post by Protoxylic
Cyclohexene is a cycloalkene. Alkenes undergo electrophilic addition with Br2 forming two C-Br bonds where the alkene pi bond was. The mechanism is the same as any old electrophilic addition, you may have learnt it with a simple alkene such as ethene, the same principal applies here.

And the last part? C6H10 + H2SO4 --> ?
Right might be a stupid question how come cyclohexene doesn't go with the standard CnH2n and not C6H12?
Original post by Super199
And the last part? C6H10 + H2SO4 --> ?
Right might be a stupid question how come cyclohexene doesn't go with the standard CnH2n and not C6H12?


Cycloalkanes such as cyclohexane are functional group isomers of their straight chain alkenes. So hexene has the same formula as cyclohexane etc. But if you now have a cycloalkene, you need to remove two extra hydrogens because a C=C bond is now present. Hence it becomes CnH2n-2. As for the sulphuric acid question, any alkene that reacts with H2SO4 at high temperature and pressure is likely to undergo an acid catalysed hydration. This means that water is added across the double bond with the intermediate species being a cyclohexane with a sulphonate substituent. The end product of this is an alcohol hence you would form cyclohexanol as your final product.
(edited 9 years ago)
Original post by Protoxylic
As for the sulphuric acid question, any alkene that reacts with H2SO4 at high temperature and pressure is likely to undergo an acid catalysed hydration. This means that water is added across the double bond with the intermediate species being a cyclohexane with a sulphonate substituent. The end product of this is an alcohol hence you would form cyclohexanol as your final product.


This is not correct.

Sulfuric acid undergoes an electrophilic addition reaction with an alkene making an alkyl hydrogen sulfate.

-C=C- + H2SO4 --> -CH-C-OSO2OH

This is how detergents are made and, as such, it is an important reaction.

These can then produce alcohols if water is added ...

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