36965-70-5Relevant articles and documents
Aerobic oxidation of p-xylene over metalloporphyrin and cobalt acetate: Their synergy and mechanism
Jiang, Quan,Xiao, Yang,Tan, Ze,Li, Qing-Hong,Guo, Can-Cheng
, p. 162 - 168 (2008)
The aerobic liquid-phase oxidation of p-xylene (PX) over metalloporphyrin and Co(OAc)2 was studied, and the co-catalysis between metalloporphyrin and Co(OAc)2 for the oxidation of PX was discovered for the first time. The results showed that both the PX conversion and terephthalic acid yield could be increased significantly despite the fact that only a minute amount of metalloporphyrin was added to the reaction mixture in addition to the Co(OAc)2 catalyst. The effects of the structure of metalloporphyrin and reaction conditions such as temperature, air pressure and catalyst concentration on the overall reaction performance were also studied. A possible mechanism for the observed synergy between metalloporphyrin and Co(OAc)2 as co-catalysts for the aerobic liquid-phase oxidation of PX was proposed based on some experimental observations. The results suggested that the PX oxidation was improved because of the acceleration of the chain initiation of PX oxidation by metalloporphyrin, and the acceleration of the chain initiation itself was due to the ease of peroxide formation over metalloporphyrin.
A preparing method of p-nitroacetophenone
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Paragraph 0042-0044, (2019/01/07)
A preparing method of p-nitroacetophenone is disclosed. The method includes reacting p-nitroethylbenzene, as a raw material, in an autoclave at 110-150 DGE C for 3-7 h under the function of a metalloporphyrin catalyst shown as a formula 1 or a formula 2 in an oxygen atmosphere having a pressure of 0.8-2 MPa under a condition of no solvent; and subjecting an obtained reaction liquid mixture to after-treatment to obtain the target product that is p-nitroacetophenone. The method includes reaction in the sealed autoclave, thus greatly reducing volatilization loss of the raw material, and avoidingemission of reaction waste gas so as to avoid environment pollution therefrom. The bionic metalloporphyrin catalyst which is naturally degradable is adopted as an auxiliary catalyst, is low in dosage,and can increase product selectivity. Consumption of an organic solvent and purification of the target product are avoided, thus reducing the cost.
Synthesis, electrochemical and spectroelectrochemical characterization of iron(III) tetraarylporphyrins containing four β, β ′-butano and β, β ′-benzo fused rings
Xu, Weijie,Fang, Yuanyuan,Ou, Zhongping,Chen, Mingyuan,Kadish, Karl M.
, p. 521 - 534 (2018/05/14)
Six iron(III) tetraarylporphyrins containing four b,b?-butano or b,b?-benzo fused rings were synthesized and characterized by electrochemistry and spectroelectrochemistry in nonaqueous media. The examined compounds are represented as butano(TpYPP)FeCl and
Iron-based metalloporphyrins as efficient catalysts for aerobic oxidation of biomass derived furfural into maleic acid
Xie, Yongdi,Huang, Yi,Wu, Chunyan,Yuan, Wenwen,Xia, Yongmei,Liu, Xiang,Wang, Haijun
, p. 20 - 27 (2018/04/05)
A series of porphyrin type catalysts with the metal active sites of Fe were prepared and investigated in aerobic oxidation of biomass-based furfural to maleic acid (MAD) in aqueous phase. The catalytic performance of meso-tetrakis(4-bromophenyl)porphyrin iron (III) chloride (FeT(p-Br)PPCl) immobilized on different supports was evaluated. It was interesting to find that the catalytic activity varied with the supports and followed the trend: FeT(p-Br)PPCl/SBA–15 > FeT(p-Br)PPCl/meso-ZSM–5 > FeT(p-Br)PPCl/MCM-41. The effect of reaction conditions were discussed in detail over FeT(p-Br)PPCl/SBA-15 catalyst, and 56.1% yield and 73.8% selectivity of MAD were obtained from renewable furfural under the optimal conditions. Moreover, the FeT(p-Br)PPCl/SBA-15 catalyst could be reused five times without a significant decrease of activity in recycling examinations.
Catalytic Aerobic Oxidation of Biomass-based Furfural into Maleic Acid in Aqueous Phase with Metalloporphyrin Catalysts
Huang, Yi,Wu, Chunyan,Yuan, Wenwen,Xia, Yongmei,Liu, Xiang,Yang, Huamei,Wang, Haijun
, p. 786 - 794 (2017/07/24)
Catalytic oxidation of renewable furfural into valuable maleic acid in aqueous solutions using metalloporphyrin catalysts was investigated for the first time. The synthesized catalysts were characterized by FT-IR, UV–vis, 1H NMR, elemental analysis, and TGA. The catalysts varied in metal active sites and functional groups, which had different effects on their catalytic activity. Furthermore, the effects of temperatures, reaction time, catalyst loading, and oxygen pressure were studied in detail. Maleic acid could be achieved in 44% yield by using FeT(p-Cl)PPCl as catalyst under optimal conditions. Finally, FeT(p-Cl)PPCl could be reused in five consecutive runs without a significant loss of activity.
Influence of substituents in meso-aryl groups of iron μ-oxo porphyrins on their catalytic activity in the oxidation of cycloalkanes
Tabor, Edyta,Po?towicz, Jan,Pamin, Katarzyna,Bas?g, Sylwia,Kubiak, W?adys?aw
, p. 342 - 349 (2016/10/09)
The aim of this work was to study the effect of substituents on the catalytic activity of iron μ-oxo porphyrins in oxidation of cycloalkanes. Electron-donating or electron-withdrawing substituents were introduced in meso-aryl groups of iron μ-oxo porphyrins. An important part of the work was the characterization of the catalysts, in particular their redox properties. Catalytic performance and selectivity were evaluated using cyclopentane, cyclohexane, and cyclooctane as model compounds. It was shown that not only electron-withdrawing but also electron-donating substituents improved the catalytic performance of iron μ-oxo complexes. Moreover, catalytic activity of iron μ-oxo porphyrins with electron-withdrawing substituents correlated with the half-wave potential E1/2while the catalytic activity of iron μ-oxo porphyrins with electron-donating substituents increased with the decrease of reduction potential ERED.
Synthesis, characterization and spectral properties of substituted tetraphenylporphyrin iron chloride complexes
Sun, Zhi-Cheng,She, Yuan-Bin,Zhou, Yang,Song, Xu-Feng,Li, Kai
experimental part, p. 2960 - 2970 (2011/06/21)
A series of substituted tetraphenylporphyrin iron chloride complexes [RTPPFe(III)Cl, R=o/p-NO2, o/p-Cl, H, o/p-CH3, o/p-OCH3] were synthesized by a novel universal mixed-solvent method and the spectral properties of free b
A green process for oxidation of p-nitrotoluene catalyzed by metalloporphyrins under mild conditions
Wang, Lanzhi,She, Yuanbin,Zhong, Rugang,Ji, Hongbing,Zhang, Yanhui,Song, Xufeng
, p. 757 - 761 (2012/12/22)
A novel synthetic technology of p-nitrobenzoic acid has been investigated with dioxygen by using metalloporphyrins RTPP-MIIICl (M = Fe, Co, Mn) as biomimetic catalysts. Oxidation of p-nitrotoluene to p-nitrobenzoic acid under 2.0 MPa of O2 in the presence of a microamount of metalloporphyrins (RTPP-MIIICl) at 55 °C was achieved with the highest (up to 90.4%) yield. Further research results show that the catalytic activities were relative to the nature of the substituted groups and the central metal ions of metalloporphyrins. For the metalloporphyrins with the same center metal ions, the greater the electron-withdrawing degree of groups in the porphyrin ring, the higher the catalytic activities of the metalloporphyrins. The catalytic activities for metalloporphyrins with different center metal ions followed the order RTPPMn IIICl > RTPP Fe IIICl > RTPP Co IIICl.
Oxochromium compounds. 1. Synthesis and properties of μ-oxo chromium-iron porphyrin and phthalocyanine compounds
Liston, David J.,Kennedy, Brendan J.,Murray, Keith S.,West, Bruce O.
, p. 1561 - 1567 (2008/10/08)
The reaction between CrIVO(P) and FeII(P′) leads to the formation of μ-oxo heterobinuclear complexes (P)CrOFe(P′) where P and P′ represent dianions of porphyrins that may be the same or different. [Abbreviations for the dianions of 5,10,15,20-tetraarylporphyrins: TPP, tetraphenylporphyrin; TTP, tetra-p-tolylporphyrin; TMP, tetrakis(p-methoxyphenyl)porphyrin; TFP, tetrakis(p-fluorophenyl)porphyrin; TCP, tetrakis(p-chlorophenyl)porphyrin; TXP, tetra-3,5-xylylporphyrin; OEP, the dianion of 2,3,7,8,12,13,17,18-octaethylporphyrin; Pc, the dianion of the phthalocyanine molecule.] The complexes react with heterocyclic Lewis bases, and these coordinate to Cr only. The visible, infrared, 1H NMR, and Mo?ssbauer spectra are reported for the compounds. The variation of magnetic susceptibility with temperature down to 4.2 K is interpreted in terms of strong antiferromagnetic coupling between Cr(III) (S = 3/2) and Fe(III) (S = 5/2) centers with J values in the range -130 to -150 cm-1. Zero field splitting effects are important at low temperatures. The reaction of CrO(TPP) with FeII(Pc) forms an analogous μ-oxo complex having porphyrin and phthalocyanine groups attached to Cr(III) and Fe(III), respectively.