52856-15-2Relevant academic research and scientific papers
Tetra- And Dinuclear Palladium Complexes Based on a Ligand of 2,8-Di-2-pyridinylanthyridine: Preparation, Characterization, and Catalytic Activity
Lin, Shih-Chieh Aaron,Liu, Shiuh-Tzung,Liu, Yi-Hung,Peng, Shie-Ming,Su, Bo-Kai
, p. 2081 - 2089 (2021)
Complexation of L [L = 5-phenyl-2,8-di-2-pyridinyl-anthyridine] with [Pd(CH3CN)4](BF4)2 and [Pd(CH3CN)3Cl](BF4) in a molar ratio of 1:2 rendered the corresponding dinuclear complexes [Pd2L (CH3CN)4](BF4)4 (1) and [Pd2L (CH3CN)2Cl2](BF4)2 (2), respectively. However, treatment of L with (COD)PdCl2 followed by anion exchange yielded a tetranuclear complex [Pd4L3Cl4](PF6)4(4a). Structures of these complexes are characterized by both spectroscopy and X-ray crystallography. Interconversion of these three complexes was studied via the manipulation of stoichiometric ratio of ligand to metal precursor. The catalytic activity of these complexes for carbonylative Suzuki-Miyaura cross-coupling was investigated. Complex 2 shows an excellent catalytic activity on the reaction of aryl iodide with arylboronic acid in the presence of atmospheric pressure of CO to give the corresponding benzophenones.
An Anthyridine-Based Pentanitrogen Donor Switches from Mono- To Tetradentate with Pd(II) Ions
Liu, Shiuh-Tzung,Liu, Yi-Hung,Peng, Shie-Ming,Su, Bo-Kai
, p. 4110 - 4119 (2021/12/17)
Treatment of 5-phenyl-2,8-bis(2-pyridinyl)anthyridine (L) with (PPh3)2PdCl2 or (dppe)PdCl2 in the presence of a silver salt resulted in the formation of [trans-(PPh3)2PdLCl](BF4) (1a), [trans-(PPh3)2PdL(MeCN)](BF4)2 (1b), [trans-(PPh3)2PdLCl](PF6) (1c),or [cis-(dppe)PdLCl](BF4) (4), respectively. The ligand L in these complexes acts as a monodentate ligand with N(10) of anthyridine binding to the metal center. In the presence of PPh3, dinuclear complexes [Pd2L(CH3CN)2Cl2](BF4)2 (2) and [Pd2L(CH3CN)4](BF4)4 (3) readily underwent dechelation to yield 1a,b, respectively, whereas the reaction of 2 with dppe gave 4. On the other hand, treatment of 1a and 4 with S8 in the presence of a sufficient amount of palladium ions provided the corresponding dinuclear complex 2. Furthermore, this kind of substitution is also applicable with the Pd-Me complex [Pd2L(CH3CN)2Me2](BF4)2 (5), which could be prepared from complexation of L with 2 equiv of [(COD)Pd(CH3CN)Me](BF4). Thus, [trans-(PPh3)2PdLMe](BF4) (7) was obtained by the reaction of 5 with PPh3. However, the reaction of PPh3 with [Pd2L(CH3CN)2(MeCO)2](BF4)2 (6), a CO insertion product of 5, gave a messy result. The catalytic activity of these complexes in the Suzuki-Miyaura coupling of aryl halide with arylboronic acid under a CO atmosphere was investigated. Crystal structures of 1c, 4, 5, and 7 are reported to confirm their structural details. This work demonstrates the novelty of L as a hypodentate ligand toward palladium ions.
An improved palladium(II)-catalyzed method for the synthesis of aryl ketones from aryl carboxylic acids and organonitriles
Axelsson, Linda,Veron, Jean-Baptiste,S?vmarker, Jonas,Lindh, Jonas,Odell, Luke R.,Larhed, Mats
supporting information, p. 2376 - 2380 (2014/05/06)
A palladium(II)-catalyzed decarboxylative protocol for the synthesis of aryl ketones has been developed. The addition of TFA was shown to improve the reaction yield and employing THF as solvent enabled the use of solid nitriles and in only a small excess. Using this method, five different benzoic acids reacted with a wide range of nitriles to produce 29 diverse (hetero)aryl ketone derivatives in up to 94% yield.
Selective synthetic routes to sterically hindered unsymmetrical diaryl ketones via arylstannanes
Lo Fiego, Marcos J.,Silbestri, Gustavo F.,Chopa, Alicia B.,Lockhart, Maria T.
experimental part, p. 1707 - 1714 (2011/05/17)
Bulky arylstannanes and bulky aroyl chlorides are good reaction partners for the synthesis of two-, three-, and even four-ortho-substituted benzophenones, in good to excellent isolated yields (47-91%). Three simple and direct routes, with differential advantages, are proposed: (i) a catalyst-free protocol, in o-dichlorobenzene (ODCB) at 180 °C; (ii) a room temperature protocol, using AlCl3 (0.5 equiv), in dichloromethane (DCM); and (iii) a solvent-free, indium-promoted procedure. A radical mechanism is proposed for the indium-mediated reactions.2011 American Chemical Society.
