[noda]

Hi
I need to know what is the rule of sodium tungstate in the oxidation of compound 40(see attachment) to compond 47?
I know that sodium tungstate is a catalyst in the reaction and it improves the yield, please explain me the mechanism of the reaction.
moreover why the solvent of the reaction is Acetic acid?
thank you for your attention

[nj_bartel]

via wiki, hopefully applies to this reaction.

In organic chemistry, sodium tungstate is used as catalyst for epoxidation of alkenes and oxidation of alcohols into aldehydes or ketones.

[noda]

I know that sodium tungstate is catalyst in this reaction but I don't understand the mechanism of the oxidation

[Artur]

Por favor, considere o mecanismo proposto no seguinte artigo:

"Oxidation of sul®des to sulfoxides and sulfones with 30%hydrogen peroxide under organic solvent- and
halogen-free conditions"
disponível em:
http://144.206.159.178/ft/986/32316/562114.pdf

Atenciosamente,
Artur

[Babcock_Hall]

Acetic acid is a solvent I see frequently in oxidation of amino acid derivatives containing sulfur.  Speculation:  One advantage in keeping the reaction acidic might be to keep the nitrogen atom fully protonated, and perhaps less prone to oxidation.