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We describe the mononuclear anionic cyanido-pentafluorophenyl complexes, (NBu4)[Pt(C^N)(C6F5)(CN)] [C^N = 7,8-benzoquinolate (bzq) 1, 2-(2,4-difluorophenyl)pyridinate (dfppy) 2] and the heteropolynuclear derivatives [{Pt(C^N)(C6F5)(CN)}Tl] (C^N = bzq 3, dfppy 4). These complexes were synthesized via a two-step modular synthesis by reaction of the corresponding potassium salts K[Pt(C^N)(C6F5)(CN)], prepared in situ from [Pt(C^N)(C6F5)(DMSO)] and KCN in acetone/H2O, with TlPF6. The structures of {[Pt(bzq)(C6F5)(CN)Tl]·THF}n (3·THF)n and [{Pt(dfppy)(C6F5)(CN)}Tl]4·dioxane [4]4·dioxane, determined by X-ray crystallography, confirm the presence of Pt(II)–Tl(I) bonds [2.9795(6)–3.0736(3) Å], but in the dfppy complex, the incorporation of dioxane, causes a significant structural change. Thus, whereas [3·THF]n achieves a bent-ladder shape extended double chain Tl⋯[Pt⋯Tl]n⋯Pt supported by lateral bridging [Pt](μ-CN)[Tl] ligands, [4]4·dioxane is formed by discrete Pt4Tl4 rectangular aggregates stabilized by [Pt](μ-CN)[Tl] and Pt⋯Tl bonds, which are connected by dioxane bridging molecules through Tl⋯O(dioxane) additional contacts. Solid state emissions are redshifted compared with the mononuclear derivatives 1 and 2 and have been assigned, with the support of theoretical calculations on Pt4Tl4 models, to metal–metal′-to-ligand charge transfer (3MM′LCT [d/s σ*(Pt, Tl) → π*(C^N)]) for 3 and mixed 3MM′LCT/3IL for 4. In fluid THF solution, the complexes are not emissive. At 77 K, 3 and 4 exhibit bright emissions attributed to the formation of bimetallic [{Pt(C^N)(C6F5)(CN)}Tl(THF)x], and anionic [Pt(C^N)(C6F5)(CN)]− fragments. Furthermore, both 3 and 4 exhibit a reversible mechanochromism with a red shift of the emissions upon crushing, suggesting some degree of shortening of metal–metal separation. Finally, complex 3 shows solvatochromic behavior with color/luminescence changes by treatment with a drop of MeOH, CH2Cl2, THF or Et2O, with shifts from 583 in 3-MeOH to 639 nm in 3-THF. However, 4 only demonstrates a bathochromic response to MeOH. [ABSTRACT FROM AUTHOR]

Cyclometalated Pt (II) complexes [PtMe(C^N)(L)], in which C^N = deprotonated 2,2′‐bipyridine N‐oxide (Obpy), 1, deprotonated 2‐phenylpyridine (ppy), 2, deprotonated benzo [h] quinolone (bzq), 3, and L = tricyclohexylphosphine (PCy3) were prepared and fully characterized. By treatment of 1–3 with excess MeI, the thermodynamically favored Pt (IV) complexes cis‐[PtMe2I(C^N)(PCy3)] (C^N = Obpy, 1a; ppy, 2a; and bzq, 3a) were obtained as the major products in which the incoming methyl and iodine groups adopted cis positions relative to each other. All the complexes were characterized by means of NMR spectroscopy while the absolute configuration of 1a was further determined by X‐ray crystal structure analysis. The reaction of methyl iodide with 1–3 were kinetically explored using UV–vis spectroscopy. On the basis of the kinetic data together with the time‐resolved NMR investigation, it was established that the oxidative addition reaction occurred through the classical SN2 attack of Pt (II) center on the MeI reagent. Moreover, comparative kinetic studies demonstrated that the electronic and steric nature of either the cyclometalating ligands or the phosphine ligand influence the rate of reaction. Surprisingly, by extending the oxidative addition reaction time, very stable iodine‐bridged Pt (IV)‐Pt (IV) complexes [Pt2Me4(C^N)2(μ‐I)2] (C^N = Obpy, 1b; ppy, 2b; and bzq, 3b) were obtained and isolated. In order to find a reasonable explanation for the observation, a DFT (density functional theory) computational analysis was undertaken and it was found that the results were consistent with the experimental findings. The kinetico‐mechanistic aspects of the oxidative addition reaction of MeI to a series of cycloplatinated (II) phosphine complexes were investigated. [ABSTRACT FROM AUTHOR]

We describe the mononuclear anionic cyanido-pentafluorophenyl complexes, (NBu 4 )[Pt(C^N)(C 6 F 5 )(CN)] [C^N = 7,8-benzoquinolate (bzq) 1, 2-(2,4-difluorophenyl)pyridinate (dfppy) 2] and the heteropolynuclear derivatives [{Pt(C^N)(C 6 F 5 )(CN)}Tl] (C^N = bzq 3, dfppy 4). These complexes were synthesized via a two-step modular synthesis by reaction of the corresponding potassium salts K[Pt(C^N)(C 6 F 5 )(CN)], prepared in situ from [Pt(C^N)(C 6 F 5 )(DMSO)] and KCN in acetone/H 2 O, with TlPF 6 . The structures of {[Pt(bzq)(C 6 F 5 )(CN)Tl]·THF} n (3·THF) n and [{Pt(dfppy)(C 6 F 5 )(CN)}Tl] 4 ·dioxane [4]4·dioxane, determined by X-ray crystallography, confirm the presence of Pt(II)-Tl(I) bonds [2.9795(6)-3.0736(3) Å], but in the dfppy complex, the incorporation of dioxane, causes a significant structural change. Thus, whereas [3·THF] n achieves a bent-ladder shape extended double chain Tl⋯[Pt⋯Tl] n ⋯Pt supported by lateral bridging [Pt](μ-CN)[Tl] ligands, [4]4·dioxane is formed by discrete Pt 4 Tl 4 rectangular aggregates stabilized by [Pt](μ-CN)[Tl] and Pt⋯Tl bonds, which are connected by dioxane bridging molecules through Tl⋯O(dioxane) additional contacts. Solid state emissions are redshifted compared with the mononuclear derivatives 1 and 2 and have been assigned, with the support of theoretical calculations on Pt 4 Tl 4 models, to metal-metal'-to-ligand charge transfer ( 3 MM'LCT [d/s σ*(Pt, Tl) → π*(C^N)]) for 3 and mixed 3 MM'LCT/ 3 IL for 4. In fluid THF solution, the complexes are not emissive. At 77 K, 3 and 4 exhibit bright emissions attributed to the formation of bimetallic [{Pt(C^N)(C 6 F 5 )(CN)}Tl(THF) x ], and anionic [Pt(C^N)(C 6 F 5 )(CN)] - fragments. Furthermore, both 3 and 4 exhibit a reversible mechanochromism with a red shift of the emissions upon crushing, suggesting some degree of shortening of metal-metal separation. Finally, complex 3 shows solvatochromic behavior with color/luminescence changes by treatment with a drop of MeOH, CH 2 Cl 2 , THF or Et 2 O, with shifts from 583 in 3-MeOH to 639 nm in 3-THF. However, 4 only demonstrates a bathochromic response to MeOH.

By changing the parameters of fluorination reaction of bisaryl-platinum(II) complexes, each possible competitive pathway of Ar-Ar and Ar-F formation can be selectively controlled. It was discovered that steric hindrance, type of fluorinating reagent, and temperature of reaction are determinants for Ar-F vs Ar-Ar bond formation pathway from bisaryl-fluoro-platinum(IV) complexes. The combination of bulky ligands such as mesityl with Selectfluor at RT leads to Ar-F bond formation in the presence of possible Ar-Ar formation.