Diketo Hydroxamic Acid Formation

[tylerngo]

Hello everyone,

I am trying to run the conversion of a diketo ester into a diketo hydroxamic acid (never described I think).
To avoid, hydrolysis product or degradation of the starting material, I chose a procedure that does not involve strong basic conditions (see scheme below).



The thing is, I don't know which product is formed.

In LCMS, I have one peak only with the mass 434

- The starting material is entirely consumed (comparison of retention times and mass)
- The corresponding methyl ketone is not regenerated (not the same retention time and mass)
- The diketo acid is not formed
- When I test the product with FeCl3, the test is positive I get a red complex

The mass missing from the product I want is 15, like a CH3 but I don't have any methanol, I wanted to avoid transesterification so I used ethanol.

Since I don't see hydrogens of OH et NH in NMR, I don't know which experiment I could use to understand the structure I formed !

Thank you for your help,

 

Brumer

[exchemist]

Hello everyone,

 

I am trying to run the conversion of a diketo ester into a diketo hydroxamic acid (never described I think).

To avoid, hydrolysis product or degradation of the starting material, I chose a procedure that does not involve strong basic conditions (see scheme below).

 

 

 

The thing is, I don't know which product is formed.

 

In LCMS, I have one peak only with the mass 434

 

- The starting material is entirely consumed (comparison of retention times and mass)

- The corresponding methyl ketone is not regenerated (not the same retention time and mass)

- The diketo acid is not formed

- When I test the product with FeCl3, the test is positive I get a red complex

 

The mass missing from the product I want is 15, like a CH3 but I don't have any methanol, I wanted to avoid transesterification so I used ethanol.

 

Since I don't see hydrogens of OH et NH in NMR, I don't know which experiment I could use to understand the structure I formed !

 

Thank you for your help,

 

Brumer

Again your drawing has not come through. A bit hard to understand what is going on without seeing the reaction scheme. But you may find a site with more working chemists on it is better than this one. I'm the only chemist here and I have only done organic synthesis problems at university.