98-80-6Relevant articles and documents
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Gilman,Moore
, p. 3609 (1958)
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Novel biscapped and monocapped tris(dioxime) Mn(II) complexes: X-ray crystal structure of the first cationic tris(dioxime) Mn(II) complex [Mn(CDOH)3BPh]OH (CDOH2 = 1,2-cyclohexanedione dioxime)
Hsieh, Wen-Yuan,Liu, Shuang
, p. 5034 - 5043 (2006)
This report describes the synthesis and characterization of a series of novel biscapped and monocapped tris-(dioxime) Mn(II) complexes [Mn(dioxime) 3(BR)2] and [Mn(dioxime)3BR]+ (dioxime = cyclohexanedione dioxime (CDOH2) and 1,2-dimethylglyoxyl dioxime (DMGH2); R = Me, n-Bu, and Ph). All tris(dioxime) Mn(II) complexes have been characterized by elemental analysis, IR, UV/vis, cyclic voltammetry, ESI-MS, and, in the cases of [Mn(CDOH)3BPh] OH·CHCl3 and [Mn(CDO)(CDOH)2(BBu(OC 2H5))2], X-ray crystallography. It was found that biscapped Mn(II) complexes [Mn(dioxime)3(BR)2] are not stable in the presence of water and readily hydrolyze to form monocapped cationic complexes [M(dioxime)3BR]+. This instability is most likely caused by mismatch between the size of Mn(II) and the coordination cavity of the biscapped tris(dioxime) ligands. In contrast, monocapped cationic complexes [M(dioxime)3BR]+ are very stable in aqueous solution even in the presence of PDTA (1,2-diaminopropane-N,N,N′,N′- tetraacetic acid) because of the kinetic inertness imposed by the monocapped tris(dioxime) chelators that are able to completely wrap Mn(II) into their N6 coordination cavity. [Mn(CDO)3BPh]OH has a distorted trigonal prismatic coordination geometry, with the Mn(II) being bonded by six imine-N donors. The hydroxyl groups from three dioxime chelating arms form very strong intramolecular hydrogen bonds with the hydroxide counterion so that the structure of [Mn(CDOH)3BPh]OH can be considered as being the clathrochelate with the hydroxide counterion as a cap .
Fourth subgroup metal complex with rigid annular bridging structure and application of fourth subgroup metal complex
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Paragraph 0058; 0061-0062, (2021/06/23)
The invention belongs to the technical field of olefin polymerization catalysts, and particularly relates to a fourth subgroup metal complex with a rigid annular bridging structure and an application of the fourth subgroup metal complex. The fourth subgroup metal complex provided by the invention has a structure represented by a formula (A) or a formula (B), X is halogen or alkyl; and M is titanium, zirconium or hafnium. On the basis of a non-metallocene catalyst, a bridging structure in catalyst molecules is improved and upgraded, and a brand-new metal complex with excellent catalytic performance and good high-temperature tolerance is designed; when the fourth subgroup metal complex is used as a main catalyst to catalyze olefin polymerization reaction, under the activation action of a small amount of mixed cocatalyst, the fourth subgroup metal complex can efficiently catalyze the copolymerization reaction of ethylene and alpha-olefin to obtain polyolefin with high molecular weight and high comonomer insertion rate.
Erratum: Linking molecular behavior to macroscopic properties in ideal dynamic covalent networks (Journal of the American Chemical Society (2020) 142: 36 (15371-15385) DOI: 10.1021/jacs.0c06192)
Iten, Ramon,Marco-Dufort, Bruno,Tibbitt, Mark W.
supporting information, p. 18730 - 18731 (2020/11/19)
The "concentration of functional groups, c,"was defined incorrectly on page S18 of the Supporting Information. The (Table Presented) correct definition is as follows: c is the concentration of functional groups of one of the two network components, assuming that both components are present in equal amounts. Therefore, in a network formed from tetrafunctional macromers (f = 4) and where the total molar concentration of macromers is [PEG], c = f [PEG]/2 = 4[PEG]/2 = 2[PEG]. In the original Supporting Information, we took c as the total concentration of functional groups in the network, resulting in c = 4[PEG]. This formula was incorrect and resulted in erroneous values for select Keq or Gp data reported in Table 1 (page 15374) and Figure 8 (page 15381). The corrected Table 1 and Figure 8 are shown below, and the SI has been corrected accordingly. In addition, some of these data that are quoted in the article should be changed as follows (with the corrected values highlighted in bold). On page 15374: "Keq,c = 37.5 when c = 0.02 M,""Keq was determined to be 540 ± 65. [?] corresponding to Gp = 10.9 ± 2.0 kPa,"and "Keq was quantified as 277 ± 37 from NMR and 323 from DFT, corresponding to Gp = 8.0 ± 0.8 and 9.0 kPa, respectively."On page 15381: "The rheometric data exhibited a similar increase in Keq from 75 at pH 6 to 10750 at pH 9 (Figure 8c)"and "At pH 9, Keq = 1126 ± 108 and 565 (from spectroscopy and rheology, respectively) and then decreased sharply at pH 10 to Keq = 112 and 120 (Figure 8e,f)."On page 15373 (in the Figure 2 caption): "Keq = 540 ± 65."'Table Presented' These corrections do not affect any of the conclusions of the article but only the exact value of select parameters. We apologize for these errors and for any inconvenience caused to the readers. ? Associated Content: ? Supporting Information The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/jacs.0c10406. Synthesis, sample preparation, computational and experimental methods, and model descriptions (PDF). (Figure Presented).