Trivalent and Tetravalent Palladium and Platinum Organometallic Complexes

Synthesis and Characterization of Palladium Pincer Bis(carbene) CCC Complexes

“…The study of organometallic palladium complexes continues to attract interest, particularly in the context of C–C and C–heteroatom bond forming reactions. − Both experimental and theoretical studies on Pd-catalyzed transformations have extensively focused on low-valent Pd 0/II systems, while catalytic processes invoking Pd II/IV cycles are a topic of complementary interest toward distinct modes of reactivity. − For example, C–halogen bond formation via reductive elimination from Pd IV centers is more thermodynamically favorable than in Pd II to generate halogenated molecules of further utility in organic synthesis − and pharmaceutical production. , However, stability is a key challenge in the isolation and characterization of high-valent Pd complexes as facile reductive elimination can lead to rapid decomposition. Thus, isolable high-valent palladium species often necessitate the incorporation of multidentate, strongly donating ligands to stabilize the +4 oxidation state. , …”

“…Thus, isolable high-valent palladium species often necessitate the incorporation of multidentate, strongly donating ligands to stabilize the +4 oxidation state. 15,16 In that regard, pincer ligands usually confer desirable properties for a catalyst on the resulting palladium com-plex�such as high thermal stability and increased water and air stability�important qualities that make the handling of these compounds relatively easy. 17 In this class of ligands, Pd complexes incorporating an aryl-linked ECE (E = N, O, S, and P) backbone are some of the most popular.…”

“…Thus, isolable high-valent palladium species often necessitate the incorporation of multidentate, strongly donating ligands to stabilize the +4 oxidation state. 15 , 16 …”