Deprotection of aryl mesylates: A new method

CHED 553

Daniel L. Silverio, dsilveri@udel.edu and D. F. Taber, taberdf@udel.edu. Department of Chemistry and Biochemistry, University of Delaware, 110 New Castle Hall, Newark, DE 19717
The mesyl group has been shown to be useful for protecting the hydroxyl group in phenols. A key issue with any protecting group is the development of a method to remove it that is facile, efficient, and preserves functionality elsewhere in the molecule. A new method developed in the Taber group uses heated diethylamine in a pressure reaction vial to accomplish this goal. A major advantage of this is that the diethylamine acts as both the solvent and the reagent in the reaction. Both the high temperature and solvent condition of this reaction makes this method ideal for mesylates that are otherwise difficult to dissolve using current methods. More nucleophilic amines, such as morpholine, are being looked at to speed up the reaction. There are initial promising results with these new bases.