reaction with bromoacetic acid

surface · Post by **surface** » Wed Feb 11, 2009 7:49 am

Hi all,

Question: I would like to carboxylate a dextran chain (long sugar chain). In literature bromoacetic acid is used for this purpose (coupling to the OH groups). Will 0.1 M NaOH be sufficient as a base in this case? What do you think?

Thanks!

Regards,

S.

expert · Post by **expert** » Sun Feb 22, 2009 8:23 pm

surface, I understand, sodium hydroxide is the most common, but not very good in this case. It's not so much about NaOH, but water that is not a good solvent in this case. Hydroxy groups of dextran will be "lost" in water. I'd recommend non-aqueous polar solvent such as DMF and soluble strong base. You can use sodium ethoxide or methoxide or even sodium hydroxide in methanol, just remove water or methanol/ethanol by initial evaporation with DMF. After evaporation (primarily at room temperature/vacuum) you can use your reagent. I hope you have methods in place to measure the level of modification.