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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: zeropoint on February 24, 2011, 12:15:15 PM

Title: Reducing an amide (to hemiaminal or amine) in the presence of an epoxide.
Post by: zeropoint on February 24, 2011, 12:15:15 PM
Anyone know a reagent to accomplish this? Li based reagents probably won't work as the lewis acidic quality will weaken the epoxide C-O bonds. Any suggestions would be awesome!
Title: Re: Reducing an amide (to hemiaminal or amine) in the presence of an epoxide.
Post by: sjb on February 24, 2011, 03:55:37 PM
Quote from: zeropoint on February 24, 2011, 12:15:15 PM
Anyone know a reagent to accomplish this? Li based reagents probably won't work as the lewis acidic quality will weaken the epoxide C-O bonds. Any suggestions would be awesome!

Pure & Appl. Chem., Vol. 68, No. 4. pp. 843-848, 1996 - KEt3BH http://dx.doi.org/10.1351/pac199668040843

G Barbe and A B Charette, J Am Chem Soc, 2008, 130, 18 describes a Hanztch pyridine style reduction, perhaps (don't have access to the full paper, sorry) http://dx.doi.org/10.1021/ja077463q
Title: Re: Reducing an amide (to hemiaminal or amine) in the presence of an epoxide.
Post by: Dan on February 24, 2011, 05:14:25 PM
DIBAL at low T ought to be highly chemoselective. There is certainly literature precedent for the efficient reduction of esters to aldehydes at -78oC in the presence of epoxides with DIBAL, so if you want to hit an amide it should be even easier.

eg. JACS, 2010, 132(8), 2542 - 2543
Title: Re: Reducing an amide (to hemiaminal or amine) in the presence of an epoxide.
Post by: Dan on February 25, 2011, 03:04:51 AM
Quote from: Dan on February 24, 2011, 05:14:25 PM
eg. JACS, 2010, 132(8), 2542 - 2543

Stupid emoticons, it's issue 8.

JACS, 2010, 132 (8 ), 2542 - 2543
Title: Re: Reducing an amide (to hemiaminal or amine) in the presence of an epoxide.
Post by: zeropoint on February 26, 2011, 10:32:16 AM
Quote from: sjb on February 24, 2011, 03:55:37 PM


G Barbe and A B Charette, J Am Chem Soc, 2008, 130, 18 describes a Hanztch pyridine style reduction, perhaps (don't have access to the full paper, sorry) http://dx.doi.org/10.1021/ja077463q

That's a great link. Unfortunately, I doubt that my amine is going to tautomerize, it's in an aromatic ring, making this reaction more difficult. Luckily, I have access to Charette and maybe can ask him more details about this. Thanks. Also, trying DIBAL-H