[Ingeniosuccinimide]

Greetings everybody, I have a theoretical question:

I'm trying to convert farnesol into ω−hydroxylated farnesol (a diol). One notable procedure involves protecting the hydroxyl group in form of ester, followed by an oxidation with SeO₂ in relatively mild conditions. However, the problem is (and also reported in literature) that the reaction produces a mixture of two hydroxylated isomers in quite modest yield (around 40%). The same reaction for a shorter chain terpene (e.g. geranol) is much more successful, which has sense.

Now, I'm considering the idea that some kind of modification of SeO₂ could maybe increase selectivity of the oxidation.

Do you know about any organmetallic selenium catalyst used for oxidation? Are there at all any selenium catalysts where selenium is used as central species and has various ligands bonded to it, like in cases of common organometallic catalysts that contain transition metals?

[discodermolide]

I'm not aware of any catalytic selenium compounds, however it can be used in catalytic amounts, according to
http://www.orgsyn.org/orgsyn/orgsyn/prepcontent.asp?prep=cv6p0946

But this may well not be applicable to your system. Chemistry is an experimental science, so try the reactions and see what you get. You may be able to optimise things to go the way you wish.
I don't need to remind you of the nasty properties of selenium compounds as well as 50% peroxide.

[Ingeniosuccinimide]

OK, thank you for the answer. Yep, I am aware that use of selenium catalysts requires effort in workup, but I still wanted to ask as I was unable to find any selenium complexes used as catalysts while searching...

I would like to hear a theoretical opinion about considering Se or its simple compounds, mostly SeO2, as a starting materials for development of organic Se catalysts, given that Se is not a d-block metal but relatively light metalloid with [Ar] 3d10 4s2 4p4 configuration. If anyone has something to comment please write.