BrokenS0ulz
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I really don't have a clue what is happening in this question. Is it an electrophilic addition? Or is it something to do with the alcohol group?
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EierVonSatan
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Where did you get this question from? :p:

It is something to do with the alcohol group then something to do with electrophilic addition.
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BrokenS0ulz
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(Original post by EierVonSatan)
Where did you get this question from? :p:

It is something to do with the alcohol group then something to do with electrophilic addition.
It's a question from a past paper. Why? :P

So the alcohol group breaks off heterolytically (idk if that's a word) leaving positive charge on CH2 so H-Cl bond breaks heterolytically making Cl- so Cl- joins onto CH2+. Then just an electrophilic addition of H-Cl across C=C bond. On a different side each time to make 2 products?

Is it really that complicated? It's only 2 marks so I would have expected some hidden trick making it much simpler. Is there one?
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EierVonSatan
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(Original post by BrokenS0ulz)
It's a question from a past paper. Why? :P
I don't immediately recognise it as A-level material.

So the alcohol group breaks off heterolytically (idk if that's a word) leaving positive charge on CH2 so H-Cl bond breaks heterolytically making Cl- so Cl- joins onto CH2+. Then just an electrophilic addition of H-Cl across C=C bond. On a different side each time to make 2 products?
Close but not quite.

HCl acts as an acid, the alcohol as a base to give Alkene-OH2+ which is then attacked by Cl- via nucleophilic substitution to lose water (good leaving group). Once you have Alkene-Cl, this can then react via electrophilic addition in the usual way to end up with two isomers as you said.

Is it really that complicated? It's only 2 marks so I would have expected some hidden trick making it much simpler. Is there one?
Not really. Could just look at the molecular formula and think ''we've lost the oxygen and we've ended up with a saturated compound, lets try drawing some random stuff'' :p:

Better to understand what's going on, though.
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BrokenS0ulz
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(Original post by EierVonSatan)
I don't immediately recognise it as A-level material.



Close but not quite.

HCl acts as an acid, the alcohol as a base to give Alkene-OH2+ which is then attacked by Cl- via nucleophilic substitution to lose water (good leaving group). Once you have Alkene-Cl, this can then react via electrophilic addition in the usual way to end up with two isomers as you said.


Not really. Could just look at the molecular formula and think ''we've lost the oxygen and we've ended up with a saturated compound, lets try drawing some random stuff'' :p:

Better to understand what's going on, though.
Ohh thanks I just tried drawing out the molecular formula of the compound before and after and then I noticed that actually it is quite simple.

Thanks for the help though
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