[nj_bartel]

This should be a pretty short synthesis, but I feel like I'm just not seeing something.  I've been assuming it starts with a HVZ reaction, but can't seem to work around the fact that you're going to selectively undergo acyl substitution before S_N2.  I'll post my list of available reactants below.

http://img6.imageshack.us/my.php?image=reactants.jpg

Thanks

[macman104]

Why do you think that?

edit: mac, I am deleting the link - avast reports a virus as well.

[nj_bartel]

Is an acyl halide not a more electrophilic species than an alkyl halide?  I don't see anything in that link that refutes what I was saying - when you treat the alkyl bromo-acyl bromide intermediate with water, the water doesn't act as an S_N2 nucleophile displacing the alkyl bromide, it acts as a nucleophile in a nucleophilic acyl substitution and knocks out the acyl bromide.

I could potentially HVZ, treat with the water/heat combo (which I think was intended to only go with the rearrangement reactions, but I could be wrong), treat with excess ammonia to both deprotonate the reformed carboxylic acid and displace the alkyl bromide, then treat with the borohydride (which would have no effect) / acid combo to reprotonate the carboxylic acid, but given this is an online assignment, I doubt that's the route they're looking for.

[macman104]

Is an acyl halide not a more electrophilic species than an alkyl halide?

Yes. 

I don't see anything in that link that refutes what I was saying - when you treat the alkyl bromo-acyl bromide intermediate with water, the water doesn't act as an S_N2 nucleophile displacing the alkyl bromide, it acts as a nucleophile in a nucleophilic acyl substitution and knocks out the acyl bromide.

Right, so you are now left with an alpha-bromo acid, which is the result of an HVZ reaction, no?

I could potentially HVZ, treat with the water/heat combo (which I think was intended to only go with the rearrangement reactions, but I could be wrong), treat with excess ammonia to both deprotonate the reformed carboxylic acid and displace the alkyl bromide, then treat with the borohydride (which would have no effect) / acid combo to reprotonate the carboxylic acid, but given this is an online assignment, I doubt that's the route they're looking for.

Hmm...that does seem a little convoluted.  Maybe I'm just tired, but I don't really see a clean route with those options.  The only way I would think to install a NH2 in that position would be through an SN2, reductive amination, or curtius rearrangement.  I don't think curtius will work, because we lose our C=O then.  So something has to happen with the first two options I believe.  I'll see if I can find time to look at it more tomorrow or in the next day or so.

[sjb]

This should be a pretty short synthesis, but I feel like I'm just not seeing something.  I've been assuming it starts with a HVZ reaction, but can't seem to work around the fact that you're going to selectively undergo acyl substitution before S_N2.  I'll post my list of available reactants below.

http://img6.imageshack.us/my.php?image=reactants.jpg

Thanks

A classic example of a picture not being worth a thousand words, please think of the searchable nature of the forum.

Why do you think that?

Edit: link deleted

Are you sure about that page? Just got a Kaspersky red flag for me

[nj_bartel]

Right, so you are now left with an alpha-bromo acid, which is the result of an HVZ reaction, no?

Correct, but that isn't where my problem was.

Hmm...that does seem a little convoluted.  Maybe I'm just tired, but I don't really see a clean route with those options.  The only way I would think to install a NH2 in that position would be through an SN2, reductive amination, or curtius rearrangement.  I don't think curtius will work, because we lose our C=O then.  So something has to happen with the first two options I believe.  I'll see if I can find time to look at it more tomorrow or in the next day or so.

Thanks; comforting to at least know it likely isn't something painfully obvious I'm missing.

A classic example of a picture not being worth a thousand words, please think of the searchable nature of the forum.

Little confused.

Would typing
1) CrO₃/H₃O⁺
2) LiAlH₄/H₃O⁺
etc.

have been beneficial in some way?

[sjb]

A classic example of a picture not being worth a thousand words, please think of the searchable nature of the forum.

Little confused.

Would typing
1) CrO₃/H₃O⁺
2) LiAlH₄/H₃O⁺
etc.

have been beneficial in some way?

It could just be me, but I tend to find imageshack images disappear after a while, so yes, listing the reagents may have been beneficial should someone come searching later on.

[gfunk]

I looked into it, and they do a HVZ followed by treatment with ammonium hydroxide.  This would work, assuming you're allowed to mix up your reagents.

It's a shame you don't have reagents for the Staudinger reaction .