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A series of cationic Pt(II) complexes with chelating bis‐carbene and P,P‐ or P,S‐ligands, viz. [(C^C)Pt(X^Y)][BF4]2 (2a–e), where C^C = methylenebis(3‐methyl‐1H‐imidazol‐1‐yl‐2‐ylidene, and X^Y = Ph2PCH2CH2PPh2 (dppe) (a), Ph2P(CH2)3PPh2 (dppp) (b), 1,2‐(Ph2P)2C6H4 (dppbz) (c), [Fe(η5‐C5H4PPh2)2] (dppf) (d), and Ph2PCH2CH2SPh (e), were synthesized and structurally characterized by NMR and MS spectroscopy and by single‐crystal X‐ray diffraction analysis. Furthermore, photophysical measurements showed that these compounds were non‐emissive at room temperature. However, when cooled to 77 K, compounds 2a, 2b and 2c showed weak luminescence in the near UV region with emission maxima in the 380–395 nm range. [ABSTRACT FROM AUTHOR]

This contribution expands the still narrow class of functional ferrocene phosphanes with polar cationic groups, focusing on the synthesis and catalytic use of a series of phosphanylferrocene ligands bearing positively charged guanidinium tags, [R2PfcCH2NHC(NH2)2]Cl (3a–d), where fc = ferrocene‐1,1′‐diyl, R = isopropyl (a), cyclohexyl (b), phenyl (c), and 2‐furyl (d). To probe the influence of phosphane substituents, these compounds were studied as supporting ligands in Pd‐catalyzed Suzuki–Miyaura cross‐coupling of acyl chlorides with arylboronic acids, in analogous coupling of aryl bromides with arylboronic acids, and in Rh‐catalyzed hydroformylation of 1‐hexene using trans‐[RhCl(CO){R2PfcCH2NHC(NH2)2‐κP}2]Cl2 complexes (4a–d) as pre‐catalysts. The outcome of the cross‐coupling reactions strongly depended on the starting materials, and no ligand generated a universally applicable catalyst when combined with Pd(OAc)2. In the hydroformylation reactions, the catalyst based on 4d led to lower conversions than all others, which performed rather similarly. Overall, the phenyl‐substituted phosphane 3c emerged as a good compromise, giving rise to reasonably efficient and stable catalysts in most cases (except for Suzuki–Miyaura biaryl cross‐couplings, wherein electron‐rich alkylphosphanes performed better than 3c). [ABSTRACT FROM AUTHOR]

A polar phosphanylferrocene donor equipped with a hydrophilic guanidinium pendant, Ph2PfcCH2NHC(NH)NH2 ·HCl ( 1·HCl; fc = ferrocene-1,1′-diyl), has been prepared from the corresponding amine hydrochloride, Ph2PfcCH2NH2 ·HCl ( 2·HCl), and studied as a ligand for PdII. The reactions of 1·HCl with [PdCl2(MeCN)2] in 1:1 and 1:2 Pd/ligand ratios led to an unexpected zwitterionic complex, [PdCl3( 1H-κ P)] ( 3), and the expected bis(phosphane) complex, trans-[PdCl2( 1H-κ P)2]Cl2 ( 4), which were structurally characterized. The defined and air-stable solvated complex 3·Me2CO and the in situ generated Pd(OAc)2/ 1·HCl system were found to be active catalysts for the Suzuki-Miyaura cross-coupling of anionic triolborates with aryl bromides, giving the corresponding biphenyls. These reactions, which do not require the presence of an additional base, were advantageously performed in aqueous ethanol, and the coupling products were isolated in good to excellent yields. [ABSTRACT FROM AUTHOR]