I am trying to synthesis a ether bond in a dimethylmaleic anhydride derivatve.
This ether bond synthesis requires an oxygen nucleophile to selectively attack bromine in presence of a base without interupt the acid anhydride (see pic in the attachment).
We have done a couple experienments to vilidate this idea.
The first one uses NaH to make the oxygen nucleophile in THF, then attack the SM. This leads to complete disappear of starting material on TLC, leaving one spot with high polarity at the starting point.
The second one mixes SM, K2CO3, the alcohol in acetone at elevated temperature (50 to 60°C) for 6 hours. This leads to incomplete reaction, giving two new spots with higher Rf then SM and one spot with high polarity at the starting point on TLC plate. I tried a flash column seperation, but the reaction mixture was too messy. The HNMR may not provide suffcient infomation to tell whether I have the desired product.
Next week, I am going to try some weaker bases such as Na2CO3, Li2CO3 and even triethylamine.
I have digged the reaxys database. There is little information I can find on literatures.
Maybe this is an infeasible approach. But I'd like to try it several more times before giving up.
I'd like to have some opinions about this reaction.
Any suggestions will be appraciated.
Thanks a lot.