[spankytank]

Hi!
I'm going to attempt to convert the aldehyde to carboxylic acid, and I'm wondering about which kind of reaction to use. An oxidation (ex. oxone) would react with the sulfide- and amine-groups. I've looked into the Cannizzaro reaction, and it seems viable. But the problem is that the reaction can only yield about 50% of desired product, and I dont have alot of aldehyde to play around with. Do any of you have a suggestion of an alternative way of converting the aldehyde group?

Thanks!

[blackcat]

Hi!
I'm going to attempt to convert the aldehyde to carboxylic acid, and I'm wondering about which kind of reaction to use. An oxidation (ex. oxone) would react with the sulfide- and amine-groups. I've looked into the Cannizzaro reaction, and it seems viable. But the problem is that the reaction can only yield about 50% of desired product, and I dont have alot of aldehyde to play around with. Do any of you have a suggestion of an alternative way of converting the aldehyde group?

Thanks!

Good question as the oxidation that normally turns aldehyde into acid will give S,S-dioxide in your case.

This is the remedy: Change CHO into CN (nitrile) by hydoxylamine, then hydrolysis. No oxidation involved.

[Babcock_Hall]

I do not know whether or not these ideas will be helpful.  However, in my experience the first oxidation of sulfur to a sulfoxide is facile, but the second oxidation can be sluggish.  In addition one might consider deliberately oxidizing to a sulfoxide as a kind of protecting group, then converting the aldehyde to a carboxylic acid.  There are reagents which can reduce a sulfoxide back to a sulfide.

[blackcat]

I do not know whether or not these ideas will be helpful.  However, in my experience the first oxidation of sulfur to a sulfoxide is facile, but the second oxidation can be sluggish.  In addition one might consider deliberately oxidizing to a sulfoxide as a kind of protecting group, then converting the aldehyde to a carboxylic acid.  There are reagents which can reduce a sulfoxide back to a sulfide.

Then Jone's reagent does the job to turn to S,S-dioxide (but not mCBPA). Then S,S-dioxide can be reduced by heating with sulfur.

[rolnor]

This could be usefull;

https://en.m.wikipedia.org/wiki/Tishchenko_reaction

Its not going to affect the sulfur or amine.
You will have to hydrolyze the ester offcourse.