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Chemistry Forums for Students => Organic Chemistry Forum => Organic Chemistry Forum for Graduate Students and Professionals => Topic started by: Babcock_Hall on November 02, 2021, 03:36:59 PM

Title: Substitution of toluene for benzene in formation of an amide
Post by: Babcock_Hall on November 02, 2021, 03:36:59 PM

Okawara T et al. 1982 Chem. Pharm. Bull. 30(4):1225-1233.
https://www.jstage.jst.go.jp/article/cpb1958/30/4/30_4_1225/_pdf
We will attempt to react a 3-carbon dibrominated acid chloride with aniline to make an amide.  The procedure that we will follow uses benzene as the solvent.  One of their substrates is quite similar to ours.  I was thinking about substituting toluene for benzene but leaving the rest of the procedure unmodified.  Does this sound reasonable?

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: wildfyr on November 02, 2021, 09:42:27 PM

Should work!

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: phth on November 03, 2021, 01:56:19 AM

benzene is not worth working with. Probably the same at the end of the day. Rather handle mercury IMHO.

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: rolnor on November 03, 2021, 05:04:49 AM

Toluene, DCM, DCE, it will work.

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: DrCMS on November 03, 2021, 11:49:50 AM

Quote from: phth on November 03, 2021, 01:56:19 AM

benzene is not worth working with.

but it smells so nice.

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: Babcock_Hall on November 03, 2021, 12:56:34 PM

As long as we are discussing this reaction, the authors did not indicate the use of a drop of DMF as a catalyst.  However my perusal of Tietze and Eicher's book mentioned this in several related reactions (synthesis of esters or amides from acid chlorides).  I am tempted to leave DMF out for simplicity, unless my yield is poor.

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: rolnor on November 03, 2021, 02:31:15 PM

Acid chlorides+amines are usually the simplest possible reactions, no catalyst is neccesary.

Title: Re: Substitution of toluene for benzene in formation of an amide
Post by: BobfromNC on November 10, 2021, 02:51:39 PM

Just did an amide formation using toluene for benzene, worked fine.  Have also used DCM instead of benzene, it worked fine also.   I just consider the solubility and workup for each reaction.

And a small drop of DMF for making the acid chloride with oxalyl chloride is fine, but not needed for many other reactions.