[TheUnassuming]

KMNO4 mediated diol formation can be tricky depending on what else you have in your molecule, have you considered forming the epoxide first then opening to form the diol?

Enthalpy: I don't think an alkene can go straight to a diol with only hydrogen peroxide, though it can be used after you form a borane intermediate (DOI: 10.1021/jo051651m).  I don't know if you can use nitrous oxide to make epoxides, but DMDO would probably do the trick.

[Enthalpy]

Thanks!

That one uses a catalyst to get the epoxy from an alkene, at 150°C and 1bar N₂O
http://www.ncbi.nlm.nih.gov/pubmed/12137519
but the more usual result seems to be a carbonyl.

[darkdevil]

Just an update. I have checked the MALDI and I found out that my product is a mixture of aldehydes, diol and a carboxylic acid in 59% 30% 11%
From the TLC, I see only 1 single spot. I which is I assumed I made my diol, but then it decomposes in aldehyde and carboxylic acid. The NMR is also strange in d-acetone, as I only observed the carboxylic acid (No aldehyde for sure; because I have an aldehyde standard of this compound and it lacks the aldehyde proton peak).