14705-63-6Relevant academic research and scientific papers
Oxidation of toluene to benzoic acid via VOTPP catalyst synthesized with an improved method
Chen, Xi,Jia, Jiaojiao,Niu, Yulan,Zhai, Lijun
, p. 1549 - 1555 (2020)
Abstract: In this paper, two-step method was used to synthesize 5,10,15,20-tetraphenyl-21H,23H-porphine vanadium(IV) oxide (VOTPP) and toluene catalytic oxidation was explored. The result showed that this catalyst led to benzoic acid as the main product and successfully simulated the reaction of toluene oxidation with the catalytic center of P-450 enzyme. Through testing the reaction conditions including used catalyst amount, temperature, pressure, and reaction time, the optimum reaction conditions were: 0.3 g VOTPP in 100 cm3 of toluene, 145 °C, 0.8 MPa, and 4 h. The conversion of toluene was 23.0% and the selectivity of benzoic acid could reach 86.0%. Its benefits lie in no solvent, mild reaction conditions, and no toxic acidic waste, making toluene oxidation a green process. Graphic abstract: [Figure not available: see fulltext.].
Scaling Up Electronic Spin Qubits into a Three-Dimensional Metal-Organic Framework
Yamabayashi, Tsutomu,Atzori, Matteo,Tesi, Lorenzo,Cosquer, Goulven,Santanni, Fabio,Boulon, Marie-Emmanuelle,Morra, Elena,Benci, Stefano,Torre, Renato,Chiesa, Mario,Sorace, Lorenzo,Sessoli, Roberta,Yamashita, Masahiro
, p. 12090 - 12101 (2018)
Practical implementation of highly coherent molecular spin qubits for challenging technological applications, such as quantum information processing or quantum sensing, requires precise organization of electronic qubit molecular components into extended frameworks. Realization of spatial control over qubit-qubit distances can be achieved by coordination chemistry approaches through an appropriate choice of the molecular building blocks. However, translating single qubit molecular building units into extended arrays does not guarantee a priori retention of long quantum coherence and spin-lattice relaxation times due to the introduced modifications over qubit-qubit reciprocal distances and molecular crystal lattice phonon structure. In this work, we report the preparation of a three-dimensional (3D) metal-organic framework (MOF) based on vanadyl qubits, [VO(TCPP-Zn2-bpy)] (TCPP = tetracarboxylphenylporphyrinate; bpy = 4,4′-bipyridyl) (1), and the investigation of how such structural modifications influence qubits' performances. This has been done through a multitechnique approach where the structure and properties of a representative molecular building block of formula [VO(TPP)] (TPP = tetraphenylporphyrinate) (2) have been compared with those of the 3D MOF 1. Pulsed electron paramagnetic resonance measurements on magnetically diluted samples in titanyl isostructural analogues revealed that coherence times are retained almost unchanged for 1 with respect to 2 up to room temperature, while the temperature dependence of the spin-lattice relaxation time revealed insights into the role of low-energy vibrations, detected through terahertz spectroscopy, on the spin dynamics.
Cycloaddition of epoxide and CO2 to cyclic carbonate catalyzed by VO(IV) porphyrin
Bai, Dongsheng,Zhang, Zhiyong,Wang, Guangjian,Ma, Fang
, p. 240 - 243 (2015)
The cycloaddition of epoxide and CO2 to synthesize cyclic carbonate catalyzed by VO(IV) porphyrin was achieved under 1.4 MPa at 150°C. The effects of reaction temperature, time, CO2 pressure, co-catalyst and porphyrin framework were investigated. The catalytic results showed that moderate to high yields of cyclic carbonates were obtained under the optimal reaction conditions.
Selective Bromination of β-Positions of Porphyrin by Self-Catalytic Behaviour of VOTPP: Facile Synthesis, Electrochemical Redox Properties and Catalytic Application
Maurya, Mannar R.,Prakash, Ved,Avecilla, Fernando,Sankar, Muniappan
supporting information, p. 1685 - 1694 (2021/05/03)
Oxidovanadium(IV) complex of β-octabromo-meso-tetraphenylporphyrin, {[VIVO(TPPBr8)], 2} was synthesized by self-catalytic oxidative bromination of meso-tetraphenylporphyrinatooxidovanadium(IV) {[VIVO(TPP), 1} in excellent yield under mild conditions at 25 °C and its structure was confirmed by single crystal X-ray study. UV-Vis and 1H NMR spectra further confirmed that the meso-phenyl rings are not brominated and thus emphasizes on the selectivity as well as synthetic importance of this catalytic method. In the presence of substrates e. g. phenol derivatives, 1 biomimics the vanadium bromoperoxidase (VBPO) enzyme and catalyses the oxidative bromination of substrates in water at 25 °C. Remarkably, 2 also catalyses the oxidative bromination of phenol derivatives under similar reaction conditions with very high turnover frequency (TOF) values (ca. 29 s?1) along with its recyclability. It was found that 2 showed superior catalytic performance as compared to 1 because of its electron deficient nature due to electron withdrawing bromo substituents and robust saddle shaped nonplanar structure (further supported by DFT studies).
Observations on the Mechanochemical Insertion of Zinc(II), Copper(II), Magnesium(II), and Select Other Metal(II) Ions into Porphyrins
Atoyebi, Adewole O.,Brückner, Christian
supporting information, p. 9631 - 9642 (2019/03/26)
Building on a proof of concept study that showed the possibility of the mechanochemical insertion of some M(II) metals into meso-tetraphenylporphyrin using a ball mill as an alternative to traditional solution-based methods, we present here a detailed study of the influence of the many experimental variables on the reaction outcome performed in a planetary mill. Using primarily the mechanochemical zinc, copper, and magnesium insertion reactions, the scope and limits of the type of porphyrins (electron-rich or electron-poor meso-tetraarylporphyrins, synthetic or naturally occurring octaalkylporphyrins, and meso-triphenylcorrole) and metal ion sources suitable for this metal insertion modality were determined. We demonstrate the influence of the experimental metal insertion parameters, such as ball mill speed and reaction time, and investigated the often surprising roles of a variety of grinding agents. Also, the mechanochemical reaction conditions that remove zinc from a zinc porphyrin complex or exchange it for copper were studied. Using some standardized conditions, we also screened the feasibility of a number of other metal(II) insertion reactions (VO, Ni, Fe, Co, Ag, Cd, Pd, Pt, Pb). The underlying factors determining the rates of the insertion reactions were found to be complex and not always readily predictable. Some findings of fundamental significance for the mechanistic understanding of the mechanochemical insertion of metal ions into porphyrins are highlighted. Particularly the mechanochemical insertion of Mg(II) is a mild alternative to established solution methods. The work provides a baseline from which the practitioner may start to evaluate the mechanochemical metal insertion into porphyrins using a planetary ball mill.
Novel synthetic method for metalloporphyrins with inorganic metal salts in high-temperature water
Sato, Takafumi,Ebisawa, Katsutoshi,Ito, Satoshi,Sue, Kiwamu,Itoh, Naotsugu
, p. 1414 - 1416 (2013/05/09)
Cobalt, nickel, copper, and oxidovanadium(2+) could be incorporated into nonpolar tetraphenyl porphyrin by using feed materials as metal sulfate, nitrate, and chloride salts and reaction in high-temperature water (423 to 673 K). Yields of metalloporphyrin
Structural Distortion of the Vanadyltetraphenylporphine Anion Radical Probed by Resonance Raman Spectroelectrochemistry
Lin, Ching-Yao,Spiro, Thomas G.
, p. 5237 - 5243 (2008/10/09)
Electronic effects of one-electron reduction are investigated for (OV)TPP (vanadyltetraphenylporphine) by the use of spectroelectrochemical techniques. Cyclic voltammetry (CV), absorption, and resonance Raman (RR) spectroscopy of the anion radical are analyzed with the aid of isotope labeling and normal-coordinate analysis (NCA) in order to understand the structural changes. The first reported Q-band excitation RR spectra of the (OV)TPP anion radical provide important information regarding the structural distortion of the porphyrin ring upon one-electron reduction, through detection of A2g modes. Direct evidence for static distortion of the porphyrin ring is provided by the lowered depolarization ratios of the A2g modes. Moreover, the upshift of the v19 vibrational mode establishes that some of the Ca-Cm bonds are strengthened in the anion. Consideration of the molecular orbital pattern shows this observation to be consistent with a B2g and not a B2g Jahn-Teller distortion. The normal-mode calculation supports this inference.
Kinetics and Mechanism of the Dissociation of the Titanyl and Vanadyl Complexes of Mesotetraphenylporphyrins
Lomova, T. N.,Berezin, B. D.
, p. 563 - 566 (2007/10/02)
Titanium(IV) and vanadium(IV) complexes of tetraphenylporphin containing O2- species as extraligands have been synthesized and purified until spectroscopically pure.The rates of dissociation of the complexes in concentrated sulphuric acid have
pH Dependence of Photovoltage at a Vanadyl Tetraphenylporphin Coated Platinum Electrode
Basu, Jyotsna,Bhattacharya, Abhijit,Das, Kaushik,Chatterjee, A. B.,Kundu, K. K.,Rohatgimukherjee, K. K.
, p. 695 - 696 (2007/10/02)
The photoresponce of a vanadyl tetraphenylporphin coated platinum electrode is dependent on pH of the solution with which it is in contact.Photocathodic behaviour is observed at lower pH whereas photoanodic behaviour is seen at higher pH.This has been explained as the combined effect of band-bending at the platinum/vanadyl tetraphenylporphin interface and adsorption of both hydrogen and hydroxyl ions at the vanadyl tetraphenylporphin/solution interface.The photoeffects remain unaltered upon removal of dissolved oxygen by nitrogen, but they are completely suppressed in the presence of hydrogen.
Vanadium(II) Porphyrin Complexes: Synthesis and Characterization. Crystal Structure of 2,3,7,8,12,13,17,18-Octaethylporphinatobis(dimethylphenylphosphine)vanadium(II)
Poncet, Jean-Luc,Barbe, Jean-Michel,Guilard, Roger,Oumous, Hassan,Lecomte, Claude,Protas, Jean
, p. 1421 - 1422 (2007/10/02)
The vanadium(II) porphyrins VII(PPhMe2)2(porp) containing phosphine ligands have been prepared from VIV(X2)(porp) porp = octaethylporphinato(oep), meso-tetraphenylporphinato, meso-tetra-m-tolylporphinato, meso-tetra-p-tolylporphinat
