Palladium-Catalyzed Synthesis of Natural and Unnatural 2-, 5-, and 7-Oxygenated Carbazole Alkaloids from N-Arylcyclohexane Enaminones

Molecules

Rafael Bautista¹  Pablo A. Montoya¹  Araceli Rebollar¹  Eleuterio Burgueño¹ 

[1] id="af1-molecules-18-10334">Departamento de Química Orgánica, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional. Prol. Carpio y Plan de Ayala, México D.F. 11340, Mexi

关键词: 2-oxygenated carbazoles;    enaminones;    palladium(II) cyclization;    clausine V;    glycoborine;   

DOI  :  10.3390/molecules180910334

来源: mdpi

【 摘 要 】

A palladium-catalyzed synthesis of the carbazole framework is described, including the preparation of 2-, 5-, and 7-oxygenated natural and unnatural carbazole alkaloids. A series of N-arylcyclohexane enaminones, generated by condensation of cyclohexane-1,3-dione with diverse anilines, were aromatized by a Pd(0)-catalyzed thermal treatment to afford the corresponding diarylamines. The latter were submitted to a Pd(II)-catalyzed cyclization and methylation processes to provide the desired carbazoles, including clausine V. Following an inverse strategy, a new and short total synthesis of glycoborine is also reported.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.