Facile Synthesis of Unsymmetrical Acridines and Phenazines by a Rh(III)-Catalyzed Amination/Cyclization/Aromatization Cascade
作者:Yajing Lian、Joshua R. Hummel、Robert G. Bergman、Jonathan A. Ellman
DOI:10.1021/ja406131a
日期:2013.8.28
annulations of aromatic azides with aromatic imines and azobenzenes to give acridines and phenazines, respectively. These transformations proceed through a cascade process of Rh(III)-catalyzed amination followed by intramolecular electrophilic aromatic substitution and aromatization. Acridines can be directly prepared from aromatic aldehydes by in situ imineformation using catalytic benzylamine.
<i>tert</i>-Butyl Bromide-Promoted Intramolecular Cyclization of 2-Arylamino Phenyl Ketones and Its Combination with Cu-Catalyzed C–N Coupling: Synthesis of Acridines at Room Temperature
2-arylamino phenyl ketones is established to supersede the traditional high-temperature, strongly acidic conditions and achieve 9-substituted acridines, by virtue of the combination of 2,2,2-trifluoroethanol and tert-butyl bromide. This protocol can be merged well with the preceding Cu-catalyzed intermolecular Chan–Evans–Lam cross-coupling reactions, therefore enabling pot-economic modular synthesis of 9-substituted