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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: vinodt on May 05, 2015, 12:48:22 PM

Title: cyano to amide conversion
Post by: vinodt on May 05, 2015, 12:48:22 PM

I would like to convert cyano group to amide selectively in presence of ester group, suggestions if any

Title: Re: cyano to amide conversion
Post by: Moi on May 06, 2015, 06:55:44 AM

You can try dissolving your nitrile in DMSO (0.3 mL/mmol), cooling to 0 ºC, and adding H2O2 30% (0.12 mL/mmol) and anhydrous K2CO3 (20 mg/mmol). Allow the mixture to warm up to r.t. In no more than 30-60 minutes your amide should be formed without hydrolize your ester group in good yield (I hope...). Add water to the mixture and purificate if necesary.

Title: Re: cyano to amide conversion
Post by: vinodt on May 06, 2015, 12:22:37 PM

Hai Moi,

Thanks for your time, i'll follow the same and hope for the best.

Title: Re: cyano to amide conversion
Post by: Moi on May 07, 2015, 04:08:04 AM

Great. Keep me abreast.

Title: Re: cyano to amide conversion
Post by: vinodt on May 08, 2015, 02:21:13 AM

Hi Moi,

Not worked, if any other alternative please let me know.
Thanks.

Title: Re: cyano to amide conversion
Post by: discodermolide on May 08, 2015, 04:34:34 AM

Why not try NaOH/H2O/EtOH/H2O2/50°C/3 h using the alcohol of your ester as a solvent?
or see here for lots of alternatives:
http://www.organic-chemistry.org/synthesis/C2O/amides.shtm (http://www.organic-chemistry.org/synthesis/C2O/amides.shtm)

Title: Re: cyano to amide conversion
Post by: orgopete on May 14, 2015, 09:05:32 AM

Quote

Not worked?

This reaction does many things. What does not worked mean? Was oxygen evolved? Was the ester hydrolyzed? Did you have ester exchange? Did you have a double bond that got oxidized? Was it no reaction?

I too was thinking of this reaction. It had several elements working for it. It directly give an amide using an oxygen nucleophile. It avoids hydroxide which will certainly hydrolyzed the ester. Peroxide is a better nucleophile than hydroxide. What went wrong?

Disco,

Quote

Why not try NaOH/H2O/EtOH/H2O2/50°C/3 h using the alcohol of your ester as a solvent?

These conditions seem quite harsh for an ester. Can you give a citation where hydrolysis did not occur?

Title: Re: cyano to amide conversion
Post by: vinodt on May 20, 2015, 07:54:22 AM

Ester group got hydrolysed, but finally succeeded by using peroxide\Amberlyst-A21 resin in methanol conditions.