Concatenating Suzuki Arylation and Buchwald–Hartwig Amination by A Sequentially Pd‐Catalyzed One‐Pot Process—Consecutive Three‐Component Synthesis of C,N‐Diarylated Heterocycles

Abstract

The concatenation of Suzukicoupling and Buchwald-Hartwiga minationi naconsecutive multicomponent reactiono pens ac oncise, modular and efficient one-pot approach to diversely functionalized heterocycles, as exemplified for 3,10-diaryl 10H-phenothiazines, 3,9-diaryl9 Hcarbazoles, and 1,5-diaryl 1H-indoles, in high yields starting from simple staringm aterials. Moreover,t his one-pot reactioni sasequentially palladium-catalyzed process that does not require additional catalystl oading after the first coupling step.

Recent Progress Concerning the N-Arylation of Indoles

“…A different approach for the preparation of diarylated indoles was reported in 2020 ( Scheme 14 ) [ 69 ]. Muller et al used 5-bromoindole to prepare diarylated indoles via sequential Suzuki reaction and Buchwald–Hartwig amination.…”

3,10‐Diaryl Phenothiazines – One‐pot Synthesis and Conformational Tuning of Ground and Excited State Electronics

“…However, sequentially palladium‐catalyzed reactions, taking advantage of a single catalyst source in a consecutive fashion in the same reaction vessel, have become a valuable tool for sustainable diversity oriented syntheses of functional molecules [22] . Recently, we established an efficient diversity‐oriented one‐pot approach to diaryl substituted heterocycles, e. g. phenothiazines, carbazoles, and indoles, concatenating Suzuki coupling and Buchwald‐Hartwig amination to a consecutive three‐component process [20] . Therefore, this novel Suzuki‐coupling‐Buchwald‐Hartwig‐amination was selected for functionalizing phenothiazines in a one‐pot fashion.…”

“…[22] Recently, we established an efficient diversityoriented one-pot approach to diaryl substituted heterocycles, e. g. phenothiazines, carbazoles, and indoles, concatenating Suzuki coupling and Buchwald-Hartwig amination to a consecutive three-component process. [20] Therefore, this novel Suzukicoupling-Buchwald-Hartwig-amination was selected for functionalizing phenothiazines in a one-pot fashion. 3-Bromo-10Hphenothiazine ( 1) as a starting material can be efficiently accessed using the optimized conditions of the Smiles rearrangement.…”

“…[13d,19] Just very recently, we disclosed a coupling-amination sequence to access diversely functionalized heterocycles by a consecutive sequentially palladium-catalyzed three-component reaction. [20] Herein, we report the coupling-amination sequence for synthesizing an expanded series of 3,10-diaryl phenothiazines via this methodology. In addition, electrochemical and photophysical properties are systematically studied by correlation analyses and as well as by quantum-chemical calculations to gain a deeper understanding of structure-property relationships of 3,10-diaryl phenothiazines derivatives.…”

“…Just very recently, we disclosed a coupling‐amination sequence to access diversely functionalized heterocycles by a consecutive sequentially palladium‐catalyzed three‐component reaction [20] . Herein, we report the coupling‐amination sequence for synthesizing an expanded series of 3,10‐diaryl phenothiazines via this methodology.…”