ABSTRACT
Direct para-selective C(sp2)-H alkylation of electron-deficient arenes based on the electroreduction-enabled radical addition of alkyl bromides has been developed under mild conditions. In the absence of any metals and redox agents, the simple electrolysis system tolerates a variety of primary, secondary, and tertiary alkyl bromides and behaves as an important complement to the directed alkylation of the C(sp2)-H bond and the classic Friedel-Crafts alkylation. This electroreduction process provides a more straightforward, environmentally benign, and effective alkylation method for electron-deficient arenes.
ABSTRACT
A general method for the synthesis of phenols from electron-deficient aryl ammonium salts or heteroaryl ammonium salts under mild conditions was developed. Benzaldehyde oxime, acetohydroxamic acid, and hydroxylamine hydrochloride were investigated as hydroxide surrogates respectively. With these hydroxide surrogates, a series of phenols were prepared in yields of 20-98%.
ABSTRACT
A metal-free convergent paired electrolysis strategy to synthesize benzylic amines through direct arylation of tertiary amines and benzonitrile derivatives at room temperature has been developed. This TEMPO-mediated electrocatalytic reaction makes full use of both anodic oxidation and cathodic reduction without metals or stoichiometric oxidants, thus showing great potential and advantages for practical synthesis. This convergent paired electrolysis method provides a straightforward and powerful means to activate C-H bonds and realize cross-coupling with cathodically generated species.