82961-67-9Relevant academic research and scientific papers
Palladium-catalyzed synthesis of natural and unnatural 2-, 5-, and 7-oxygenated carbazole alkaloids from N-arylcyclohexane enaminones
Bautista, Rafael,Montoya, Pablo A.,Rebollar, Araceli,Burgueno, Eleuterio,Tamariz, Joaquin
, p. 10334 - 10351 (2013/10/22)
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.
Orthogonal Cu- and Pd-based catalyst systems for the O- and N-arylation of aminophenols
Maiti, Debabrata,Buchwald, Stephen L.
supporting information; experimental part, p. 17423 - 17429 (2010/03/25)
O- or N-arylated aminophenol products constitute a common structural motif in various potentially useful therapeutic agents and/or drug candidates. We have developed a complementary set of Cu- and Pd-based catalyst systems for the selective O- and N-arylation of unprotected aminophenols using aryl halides. Selective O-arylation of 3- and 4-aminophenols is achieved with copper-catalyzed methods employing picolinic acid or CyDMEDA, trans-N,N′-dimethyl-1,2- cyclohexanediamine, respectively, as the ligand. The selective formation of N-arylated products of 3- and 4-aminophenols can be obtained with BrettPhos precatalyst, a biarylmonophosphine-based palladium catalyst. 2-Aminophenol can be selectively N-arylated with CuI, although no system for the selective O-arylation could be found. Coupling partners with diverse electronic properties and a variety of functional groups can be selectively transformed under these conditions.
