Palladium-Catalyzed C(sp3)–H Arylation of Diarylmethanes at Room Temperature: Synthesis of Triarylmethanes via Deprotonative-Cross-Coupling Processes

Citations Over TimeTop 1% of 2012 papers

Abstract

Although metal-catalyzed direct arylation reactions of non- or weakly acidic C-H bonds have recently received much attention, chemists have relied heavily on substrates with appropriately placed directing groups to steer reactivity. To date, examples of intermolecular arylation of unactivated C(sp(3))-H bonds in the absence of a directing group remain scarce. We report herein the first general, high-yielding, and scalable method for palladium-catalyzed C(sp(3))-H arylation of simple diarylmethane derivatives with aryl bromides at room temperature. This method facilitates access to a variety of sterically and electronically diverse hetero- and nonheteroaryl-containing triarylmethanes, a class of compounds with various applications and interesting biological activity. Key to the success of this approach is an in situ metalation of the substrate via C-H deprotonation under catalytic cross-coupling conditions, which is referred to as a deprotonative-cross-coupling process (DCCP). Base and catalyst identification were performed by high-throughput experimentation (HTE) and led to a unique base/catalyst combination [KN(SiMe(3))(2)/Pd-NiXantphos] that proved to efficiently promote the room-temperature DCCP of diarylmethanes. Additionally, the DCCP exhibits remarkable chemoselectivity in the presence of substrates that are known to undergo O-, N-, enolate-, and C(sp(2))-H arylation.

Related Papers

• → Deprotonative cadmation of functionalized aromatics(2008)80 cited
• → One-step introduction of terminal sulfonic groups into a proton-conducting metal–organic framework by concerted deprotonation–metalation–hydrolysis reaction(2020)12 cited
• → Half-sandwich iron(ii) complexes with protic acyclic diaminocarbene ligands: synthesis, deprotonation and metalation reactions(2017)7 cited
• → Regioselectivity of metalation of alkylmercaptoolefins(1979)19 cited
• → Selectivity in Organic Chemistry—Chemoselectivity(2020)