Process for producing redox shuttles
The invention provides a method for preparing 1,4-di-tert-butyl-2,5-bis(2-methoxyethoxy)benzene, the method comprising reacting 2,5-di-tert-butylbenzene-1,4-diol with cesium carbonate and halogenated ether in dimethyl formamide. The method yields 500 gram batches at a time, or multiples thereof. The method enables the industrial production of redox shuttles for use in lithium ion battery systems.
1. A method for preparing a redox shuttle, the method comprising utilizing 2,5-di-tert-butylbenzene-1,4-diol in an alkylation reaction mixture to create 1,4-di-tert-butyl-2,5-bis(2-methoxyethoxy)benzene wherein the alkylation reaction is initiated with a base having a pKa of between about 8 and 10, wherein the base confers a solubility to a 2,5-di-tert-butylbenzene-1,4-diol salt in the mixture of at least about 0.1 M.
2. The method as recited in claim 1 wherein the base is solvated with a polar aprotic solvent.
3. The method as recited in claim 2 wherein the polar aprotic solvent is a material selected from the group consisting of dimethylformamide, dimethyl acetamide, N-methylpyrrolidinone), dimethyl sulfoxide, sulfolane, and combinations thereof.
4. The method as recited in claim 2 wherein the aprotic solvent is DMF.
5. The method as recited in claim 1 wherein the method requires no anhydrous solvent.
6. The method as recited in claim 1 wherein the redox shuttle is prepared in about 6 to 7 hours.
7. A method for preparing 1,4-di-tert-butyl-2,5-bis(2-methoxyethoxy)benzene, the method comprising reacting 2,5-di-tert-butylbenzene-1,4-diol with cesium carbonate and halogenated ether in dimethyl formamide.
8. The method as recited in claim 7 wherein the method occurs in ambient atmosphere.