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Topic: Strange Amine Reactions  (Read 5692 times)

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Offline Arait

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Strange Amine Reactions
« on: April 22, 2011, 02:17:12 PM »
These three particular problems from my online homework are giving me problems. 

1.  This one is giving me issues because I can find NOWHERE online, in my textbook, or in my notes what you're supposed to do with a secondary amine plus NaNO2/HCl.  You can't really make a diazonium ion on a secondary amine, so it's confusing the heck out of me.



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2.  This one is also giving me a headache.  I've tried connecting the CH3CH2- group everywhere on this molecule, and it's never correct.  Once again, not something I can find a solution to in my book or online.



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3.  Finally, this one:

 The alkaloid coniine has been isolated from hemlock and purified. Its molecular formula is C8H17N. Treatment of coniine with excess methyl iodide, followed by silver oxide and heating, gives the pure S enantiomer of N,N-dimethyl-7-octen-4-amine. Propose a complete structure for coniine.
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Offline Honclbrif

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Re: Strange Amine Reactions
« Reply #1 on: April 22, 2011, 05:10:16 PM »
1. What's the mechanism of diazotization? What might happen if it can't go all the way?

2. If it's not adding anything, is it taking anything away?

3. Work it backwards.
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Offline Kadabrium

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Re: Strange Amine Reactions
« Reply #2 on: April 23, 2011, 06:31:13 AM »
1 could be a nitroso substituted tertiary amine R2N-NO
2 is N-MgBr..
3 it's a hofmann elim and could be (2S)-2-propylpiperidine..
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Offline Arait

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Re: Strange Amine Reactions
« Reply #3 on: April 23, 2011, 09:55:20 AM »
Thanks!  I've got 'em figured out.

Also, if either or you (or anyone else) knows what to do with this, I would love to know:

For the first one, I supposed to figure out the starting materials (if it's a Micheal reaction), and the second one, I just don't know...



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Offline jake.n

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Re: Strange Amine Reactions
« Reply #4 on: April 23, 2011, 12:37:54 PM »
For the first one, assume that the bond I hashed through is the new C-C bond formed by a Michael reaction.  Which part of this molecule would make the better nucleophile?  Which part would make the best Michael acceptor?

The second question doesn't make any sense.  Are those two starting materials meant to condense into one product?  The first molecule looks like it would be perfect for an intermolecular condensation.  The second one looks like it would polymerize under basic conditions, forming the substituted enone first, then the disubstituted ketone.  Using the two together doesn't look like it would be synthetically useful.

Anyone else have other thoughts on those two molecules?
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Offline Arait

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Re: Strange Amine Reactions
« Reply #5 on: April 23, 2011, 01:56:15 PM »
Well, this might help you.  There was another problem very similar to this one, and I happened to find the answer online.  Here's that problem and the answer.  I got the points, but I still don't understand exactly how they came to the answer:



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