An efficient and practical method for the synthesis of medicinally important acridines from readily available o-aminoaryl ketones and arylboronic acids was developed using copper(II)-mediated relay reactions that involve intermolecular Chan–Lam cross-coupling and subsequent intramolecular Friedel–Crafts-type reactions. A sole promoter, i.e., Cu(OTf)2, was used; therefore, strongly acidic and basic
Auto-Tandem Catalysis: Synthesis of Acridines by Pd-Catalyzed C=C Bond Formation and C(<i>sp<sup>2</sup></i>)-N Cross-Coupling
作者:Zhongxing Huang、Yang Yang、Qing Xiao、Yan Zhang、Jianbo Wang
DOI:10.1002/ejoc.201201070
日期:2012.10.10
A facilepalladium-catalyzedsynthesis of acridines has been realized by consecutive C=C double bondformation and C–N cross-coupling. A variety of functionalized acridines can be accessed from easily available o-dihalobenzenes and N-tosylhydrazones in a single operation. This one-pot protocol has a wide scope with respect to both coupling partners, and provides an efficient route to functionalized
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.
A facileoxidative annulation of cyclohexanones and 2‐aminophenyl ketones that uses molecular oxygen as the sole oxidant is described. The reaction provides a direct approach to acridines, a structural motif for a large number of fluorescent sensors, functional materials, ligands, and pharmaceuticals. In the presence of a palladium catalyst, high regioselectivity is observed when using non‐symmetric
<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