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Chemistry help

3D8EB03C-0FE1-42FA-9708-87D3E4F8F651.jpg.jpeg
Someone explain how the answer is D?
Reply 1
Anyone?
Reply 2
Please someone help
Moved to the chemistry forum :smile:
Reply 4
Still no answer :frown:
It's just a big complicated nucleophilic substitution reaction...

Ammonia will attack the carbon of one of the C-Br bonds with its lone pair, and so it'll replace Br with NH2
However, this NH2 group can do exactly the same thing with the other C-Br bond

If you follow it through -- you don't even need to complete the mechanism -- you'll see that the answer has to be D in order to produce coniine this way
Reply 6
Original post by Kian Stevens
It's just a big complicated nucleophilic substitution reaction...

Ammonia will attack the carbon of one of the C-Br bonds with its lone pair, and so it'll replace Br with NH2
However, this NH2 group can do exactly the same thing with the other C-Br bond

If you follow it through -- you don't even need to complete the mechanism -- you'll see that the answer has to be D in order to produce coniine this way


But how do you get a cyclic compound (coniine) from an acyclic compound (1,5-dibromooctane). I’m really confused about this and still don’t get how the answer is D. Also as far as I know, a nucleophilic substitution with ammonia will produce an amine as it will go through the NH3 intermediate then lose the hydrogen to become NH2. But this compound (coniine) only contains one hydrogen so how come?

If you could please explain this that would be appreciated. Thanks
(edited 4 years ago)
Original post by mani93786
But how do you get a cyclic compound (coniine) from an acyclic compound (1,5-dibromooctane). I’m really confused about this and still don’t get how the answer is D. Also as far as I know, a nucleophilic substitution with ammonia will produce an amine as it will go through the NH3 intermediate then lose the hydrogen to become NH2. But this compound (coniine) only contains one hydrogen so how come?

If you could please explain this that would be appreciated. Thanks

20190528_010620.jpg

Here's the mechanism for the reaction
As you can see, yes an amine is formed... But the NH2 group in the amine can also react with the other C-Br bond as well
All this is shown in the image
I read cocaine lol sorry I’m no help
Reply 9
Original post by Kian Stevens
20190528_010620.jpg

Here's the mechanism for the reaction
As you can see, yes an amine is formed... But the NH2 group can also react as well
All this is shown in the image


Thank you so much!!
Original post by mani93786
Thank you so much!!

I'm glad you've finally got your problem sorted...! :smile:
Reply 11
So it’s a secondary amine? What would be it’s IUPAC name?
Original post by mani93786
So it’s a secondary amine? What would be it’s IUPAC name?

Yes it's a secondary amine

Its IUPAC name is 2-propylpiperidine

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