Oxidation Jones Reagent Mechanism

[@XxxP0-b8h]

I'm confused. Why would the the oxygen atom of the chromium ester give e- pair to form another bond to Cr? Wouldn't that make C=O=Cr instead?

[@rimmyblumpkin5858]

+Phuong Le You are correct he drew the arrow incorrectly. He should have drawn the bond from oxygen to Cr breaking and being "donated" to Cr. That whole group leaves and leaves behind the product that he has drawn a ketone.

[@Deepikasharma-gb2yz]

How is that possible 🤔 ketone having one oxygen and. Chromium having 4 O atom at the end whereas chromium ester having 4 total Oatom

[@Spextori]

He drew the arrows incorrectly. The electrons after elimination of the alpha hydrogen atom are donated to the C-O bond, thus the O-Cr bond breaks resulting in Cr=O(OH)2 as a leaving group with apparently 3 oxygen atoms and a ketone with one oxygen atom.

[@koteshchem]

fantastic video

[@gadrri1167]

In step 1, wouldn’t the oxygen with the negative charge be more nucleophilic and attack the H+ from the acid instead of the pi bond attacking from the other carbon?

[@Spextori]

You mean, the hydrogen chromate ion should attack itself?

[@Clutchprep]

Hey there! It might look like that the negatively charged O appear as the nucleophile here but the partial positive charge of Cr is what favors the attack of the O of the -OH group. Sure, your suggestion might actually happen and form H2CrO4 but it will dissociate again and be back as HCrO4-

[@shrinetrsinghsingh1659]

What is the structure of Jones reagent???

[@Spextori]

Jones reagent consists of chromium trioxide and sulfuric acid dissolved in a mixture of acetone and water.

[@rzz1910]

you shouldnt draw any negative charge in a acidic condition.

[@Clutchprep]

+Ryan Zhou Hey! Correct, we know in acidic conditions there would be lots of H positive around where here Johnny decided to show how the negative charge would be used to form a double bond and kick out our water. Either way just know this is the basics of this mechanism with different variations. At some part in the mechanism there will be some anionic intermediate formed, but it will not stay so for long. The most important part of the oxidation is that we are forming a new bond to our oxygen in the final product :)