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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: brettlawrie on March 09, 2012, 08:40:56 PM

Title: Oxidation of Acetophenone (No Solid Observed)
Post by: brettlawrie on March 09, 2012, 08:40:56 PM

My lab partner and I performed an experiment regarding hypochlorite oxidation of acetophenone by the haloform reaction. The attached mechanism provides context.

I am stumped as to why no solid (chloroform) was observed during the oxidation of acetophenone in the provided reaction, when a solid (iodoform) was clearly observed in a similar reaction (the second attached picture) with acetone and an iodine source. Can anyone point me in the right direction as to why no solid was formed in the first reaction?

My unsure answer right now: the carbanion bonded to three chlorines is not a very good nucleophile (I am not sure why) and cannot deprotonate the OH group attached to the carboxylic acid. Therefore, H⁺ must be reintroduced (ending the oxidation part of the reaction) to form the solid chloroform. The second reaction's carbanion is a good nucleophile (not sure why) and therefore can synthesize the iodoform by itself.

Thank you for your help.

Title: Re: Oxidation of Acetophenone (No Solid Observed)
Post by: discodermolide on March 09, 2012, 11:32:55 PM

Chloroform is a liquid, that's why you did not see a solid!!!

Title: Re: Oxidation of Acetophenone (No Solid Observed)
Post by: brettlawrie on March 10, 2012, 02:34:47 AM

Quote from: discodermolide on March 09, 2012, 11:32:55 PM

Chloroform is a liquid, that's why you did not see a solid!!!

Doi.  ::)

Thanks for the help.