A Three‐Way Switchable Process for Suzuki Cross‐Coupling, Hydrodehalogenation, or an Assisted Tandem Hydrodehalogenation and Suzuki Cross‐Coupling Sequence

Abstract

A three-way switchable Pd-catalyzed and microwave assisted process appropriate for selective arylation or hydrodehalogenation of the imidazole backbone was discovered and entirely optimized. The "arylation switch position" was adapted and optimized for the synthesis of 4,5-diaryl-1H-imidazoles, while the "hydrodehalogenation switch position" was used for the preparation of 4(5)-iodo-1H-imidazole. The hydrodehalogenation and the cross-coupling reactions were also successfully combined in "the third switch position" that performs an assisted tandem reaction sequence that produced 4(5)-aryl-1H-imidazole. All of the three pathways produced their corresponding products in excellent yield.

4‐Alkylated Silver–N‐Heterocyclic Carbene (NHC) Complexes with Cytotoxic Effects in Leukemia Cells

“…Along with this work, we have revealed new synthetic methods for imidazole functionalization that include selective halogenation,23 Suzuki cross-coupling,24 Stille coupling,25 and a method for Sonogashira coupling,26 the latter of which was used in the study described herein.…”

Eco-Friendly Physical Activation Methods for Suzuki–Miyaura Reactions

“…Sandtorv and Bjørsvik [39] have reported the first three-way switchable Pd-catalyzed protocol for the selective arylation and hydrodehalogenation of imidazole backbones. Using these MW promoted strategies, they prepared a wide range of 4,5-diaryl-and 4(5)-iodo-1H-imidazoles via the selective arylation and the hydrodehalogenation of the imidazole backbone, respectively.…”

“…The author realized that hydrodehalogenation and cross-coupling processes could be coupled into a "dose-promoted" MW assisted tandem reaction in which the "trigger" for the subsequent catalytic cycle was a rise in the base and catalyst loadings to achieve a mono-arylated imidazole in excellent yields (83%). Sandtorv and Bjørsvik [39] have reported the first three-way switchable Pd-catalyzed protocol for the selective arylation and hydrodehalogenation of imidazole backbones. Using these MW promoted strategies, they prepared a wide range of 4,5-diaryl-and 4(5)-iodo-1H-imidazoles via the selective arylation and the hydrodehalogenation of the imidazole backbone, respectively.…”

Controlling the Course of a Two‐Way Switchable Pd‐Catalyzed Process by means of Empirical Multivariate Models

“…[13] From this investigation, we identified KOH as the optimal base. We also obtained the methoxydeiodinated compound 3a,aproduct that was not observed during our previous study.…”

“…[13] The attained results and potentialo ft his process encouraged us to undertake the investigation disclosed herein, which includes the exploration of the general validity and scope of the method, exploiting haloarenesi nstead of diiodoimidazoles as substrates. [13] The attained results and potentialo ft his process encouraged us to undertake the investigation disclosed herein, which includes the exploration of the general validity and scope of the method, exploiting haloarenesi nstead of diiodoimidazoles as substrates.…”