A Convenient Method for Direct N-tert-Butylation of Aromatic Amines

摘要

Although the synthesis of tert-butyl ethers by acid-catalyzed reaction of an alcohol and a tert-butyl cation source is one of the classical methods of organic chemistry, the corresponding tert-alkylation reaction of primary or secondary amines has notproven generally useful. Acids strong enough to generate tert-butyl cations from isobutylene first protonate the more basic amine, rendering it non-nucleophilic. Previously reported conditions suffer from low conversion and/or, for aromatic substrates,produce substantial amounts of ring-alkylated materials. We disclose in this paper a convenient one-step method for N-tert-butylation of aromatic amines.