[cks133]

Hi,

I'm attempting to sulphonate an allyl ether group immobilised on a solid agarose support
Allyl gylgidyl ether reaction with hydroxyl group is the precursor to the sulphonation reaction.

The standard reaction method is with sodium metabisulphite in an acetate buffer although we have attempted other sulphonating agents (sodium bisulphite/sodium sulphite/ sulphur trioxide pyridinium salt) with varying degrees of success.

The problem is, I am having problems achieving a consistent sulphonation level on repeating the reaction (As measured by titration with NaOH).

Can anyone explain the mechanism for this reaction?

Is there anything unusual that could quench this reaction or slow it down in some way. Or cause the variation seen?

Can anyone suggest alternative sulphonation methods?
Bearing in mind the reactions must be in water and at no higher than 60°C.


Thanks in advance for any help !!!