Tuesday, July 14, 2009

Allyl Amines - A Long Standing Problem

According to a recent journal article I read, allyl amines are among the most useful of synthetic intermediates. I happen to agree. If only there were a convenient and cost-effective way to make these compounds. Let me think. OK. Amines are good nucleophiles. And allyl halides are great electrophiles. Maybe if I mixed those together, I could get my precious allyl amine.

No. You idiot. That is way too complicated. There is a MUCH easier way. Just mix this "simple" gold catalyst with your amine and an allene at 100 degrees for 12 hours. And BAM! you got an allyl amine.

But wait you ask. What about other allenes than the one in the abstract picture above. Don't worry, they tried those too.

Finally, an easy way to make N-allyl morpholine! Check out the awesome E/Z selectivity with unsymmetrical allenes! Allenes as starting materials, what a great idea! They are so easy to make, especially these low molecular weight ones!

The world was waiting for a solution to this long standing problem in organic chemistry. Thank you for this. Nobel! Nobel!

Tip of the hat to Dr. B. Mike O'Keefe for pointing out this gem.


Dr. Miller said...

I know that some (i.e. Jason) will point out that over alkylation could be a problem with the amine + allyl halide suggestion. I agree. But nowhere in the paper do they use a precious amine. I have done a similar reaction with 5 eq amine and 1 allyl bromide. This paper sucks ass. Org lett is the new tet lett.

John said...

Kenny, I think it is about time you change your name to Prof. Dr. Miller

james said...

what's BMO?

Mike said...

James you really know how to piss me off....haha j/k. James' comment is in reference to a question stated by SFM during group meeting. After 5 yrs, he still has no idea who I am.

Thanks for the shout-out K. This paper seriously sucks.

Mike said...

Kenny, your sarcasm has made my day. Love it.

Jim said...

5 eq. of amine, now that's really practical.

So what, no one should ever publish a new method unless they are using it on an intermediate 15 steps in after trying everything else known to man?

scientist 1 said...

I don't know what you're complaining about Hern. Prof. Doktor Miller.

Aside from the poor substrate scope, need to make the catalyst, catalyst cost, and apparent need for deactivated/sterically hindered primary amines it looks pretty sweet.

Jim said...

Accoring to Org. Lett. today you can use the intramolecular varient to make swainsonine.

scientist 1 said...

Ooooo, BURN!

They didn't even use any sort of crazy, homemade ligand. I mean, who wants that? Waaaay too easy if you ask me.

I like how at the end of the synthesis they were unable to allylate the amine under standard conditions, and used an alloc degradation instead. Why use the same method twice in the same synthesis? Especially if it's the point of the paper.