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In this paper, a synthesis of two innovative coordination compounds, based on chromium(III) and cobalt(II) ions with N,O-donor ligands (nitrilotriacetate, dipicolinate) and 4-acetylpyridine, is reported. The obtained metal-organic compounds were structurally characterized using the single-crystal X-ray diffraction (XRD) method. The well-defined chromium(III) and cobalt(II) complexes were used as precatalysts in the oligomerization reaction of 2-chloro-2-propen-1-ol and 2-propen-1-ol with methylaluminoxane (MMAO) as an activator. The products of the oligomerization reaction were subjected to full physicochemical characteristics, i.e., time-of-flight mass spectrometry (MALDI-TOF-MS), TGA, and differential scanning calorimetry (DSC) methods. The catalytic activity of the precatalysts in both reactions was calculated and compared with other catalysts known in the literature. [ABSTRACT FROM AUTHOR]

Designing catalyst systems based on transition metal ions and activators using the principles of green chemistry is a fundamental research goal of scientists due to the reduction of poisonous solvents, metal salts and organic ligands released into the environment. Urgent measures to reduce climate change are in line with the goals of sustainable development and the new restrictive laws ordained by the European Union. In this report, we attempted to use known oxovanadium(IV) green complex compounds with O, N and S donor ligands, i.e., [VO(TDA)phen] • 1.5 H2O (TDA = thiodiacetate), (phen = 1,10-phenanthroline), oxovanadium(IV) microclusters with 2-phenylpyridine (oxovanadium(IV) cage), [VOO(dipic)(2-phepyH)] • H2O (dipic = pyridine-2,6-dicarboxylate anion), (2-phepyH = 2-phenylpyridine), [VO(dipic)(dmbipy)] • 2H2O (dmbipy = 4,4′-dimethoxy-2,2′-dipyridyl) and [VO(ODA)(bipy)] • 2 H2O (ODA = oxydiacetate), (bipy = 2,2′-bipyridine), as precatalysts in oligomerization reactions of 3-buten-2-ol, 2-propen-1-ol, 2-chloro-2-propen-1-ol and 2,3-dibromo-2-propen-1-ol. The precatalysts, in most cases, turned out to be highly active because the catalytic activity exceeded 1000 g mmol−1·h−1. In addition, the oligomers were characterized by Fourier-transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization (MALDI-TOF-MS), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. [ABSTRACT FROM AUTHOR]

The thermal stability of the oligomers obtained by using 2-chloro-2-propen-1-ol as the monomer has been studied. The oligomers were synthesized using chromium(III) and oxovanadium(IV) complexes as the catalysts after activation by modified methylaluminoxane (MMAO-12). The complexes used as the catalysts were polycarboxylate complex compounds of oxovanadium(IV) and chromium(III). The studies have been conducted by two methods: thermal gravimetry and differential scanning calorimetry. The obtained results allow to determine the glass transition temperatures and thermal stability of the oligomers depending on the central catalyst cation Cr3+ and V4+. [ABSTRACT FROM AUTHOR]

The contemporary search for new catalysts for olefin oligomerization and polymerization is based on the study of coordinating compounds and/or organometallic compounds as post-metallocene catalysts. However known catalysts are suffered by many flaws, among others unsatisfactory activity, requirement of high pressure or instability at high temperatures. In this paper, we present a new catalyst i.e. the crystalline complex compound possesing high catalytic activity in the oligomerization of olefins, such as 2-chloro-2-propen-1-ol and ethylene under very mild conditions (room temperature, 0.12 bar for ethylene oligomerization, atmospheric pressure for 2-chloro-2-propen-1-ol oligomerization). New material—Cat-CrNP ([nitrilotriacetato-1,10-phenanthroline]chromium(III) tetrahydrate) has been obtained as crystalline form of the nitrilotriacetate complex compound of chromium(III) with 1,10-phenanthroline and characterized in terms of its crystal structure by the XRD method and by multi-analytical investigations towards its physicochemical propeties The yield of catalytic oligomerization over Cat-CrNP reached to 213.92 g · mmol−1 · h−1· bar−1 and 3232 g · mmol−1 · h−1 · bar−1 for the 2-chloro-2-propen-1-ol and ethylene, respectively. Furthemore, the synthesis of Cat-CrNP is cheap, easy to perform and solvents used during preparation are environmentally friendly. [ABSTRACT FROM AUTHOR]

Polyolefins are used in everyday life, including in the production of many types of plastic. In addition, polyolefins account for over 50% of the polymers produced in the world. After conducting the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene, polyolefins are obtained. In this report, two complexes of oxovanadium(IV) and dioxovanadium(V) with dipicolinate, 2-phenylyridine, and 4,4′-dimethoxy-2,2′-bipyridyl as precatalysts for 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norborene oligomerizations are prepared. We present for the first time the new dipicolinate complex compound of oxovanadium(IV) with 4,4′-dimetoxy-2,2′-bipyridyl. Both complexes were tested for catalytic activity in the oligomerization reactions of 2-propen-1-ol, 2-chloro-2-propen-1-ol, and norbornene. Both synthesized complexes showed high catalytic activity in these oligomerization reactions, except for the oligomerization of norbornene. [ABSTRACT FROM AUTHOR]

Currently, new precatalysts for olefin oligomerization are being sought in the group of vanadium(IV) complexes. Thus, the aim of our research was to examine the catalytic activity of the oxovanadium(IV) dipicolinate complex [VO(dipic)(H2O)2] 2 H2O (dipic = pyridine-2,6-dicarboxylate anion) in 2-propen-1-ol oligomerization as well as to characterize oligomerization products using matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF-MS), infrared spectroscopy (IR) and nuclear magnetic resonance (NMR). The oligomerization process took place at room temperature, under atmospheric pressure and under nitrogen atmosphere to prevent oxidation of the activator MMAO-12—the modified methylaluminoxane (7 wt.%) aluminum in toluene. The last point was to determine the catalytic activity of the complex in the oligomerization reaction of 2-propen-1-ol. The aspect that enriches this work is the proposed mechanism of oligomerization of allyl alcohol based on the literature. [ABSTRACT FROM AUTHOR]

So far, few microclusters containing vanadium have been described in the literature. In this report, the synthesis protocol for the preparation of oxovanadium (IV) microclusters with 2-phenylpyridine is shown for the first time. Moreover, the crystal structure of these microclusters is also studied through the use of X-rays. The morphology of the prepared crystals is investigated using a field-emission Scanning Electron Microscope (SEM). The new compound, after activation by modified methylaluminoxane as the catalytic system, is investigated regarding the oligomerizations of 3-buten-1-ol, 2-chloro-2-propen-1-ol, allyl alcohol, and 2,3-dibromo-2-propen-1-ol. The products of oligomerization are tested by the TG-FTIR and MALDI-TOF-MS methods. Moreover, the values of catalytic activities for the new oxovanadium(IV) microclusters with 2-phenylpyridine are determined for the 3-buten-1-ol, 2-chloro-2-propen-1-ol, allyl alcohol, and 2,3-dibromo-2-propen-1-ol oligomerizations. Oxovanadium(IV) microclusters with 2-phenylpyridine are shown to be very highly active precatalysts for the oligomerization of allyl alcohol, 2,3-dibromo-2-propen-1-ol, and 3-buten-1-ol. However, in the case of 2-chloro-2-propen-1-ol oligomerization, the new microclusters are seen as highly active precatalysts. [ABSTRACT FROM AUTHOR]

The report focuses on the new precatalysts for ethylene oligomerization. The five chromium(III) complex compounds containing the following ligands: dipicolinate anion, oxalate anion, 5-aminopyridine-2-carboxylate anion, 2,2′-bipyridine and 4,4′-dimethoxy-2,2′-bipyridine have been examined towards catalytic activity for ethylene oligomerization. The chromium(III) complexes have been activated by modified methylaluminoxane. The obtained oligomers have been investigated by MALDI-TOF–MS, thermal analysis and infrared spectroscopy. The results revealed that the examined chromium(III) complexes are highly active catalysts for ethylene oligomerization. The values of catalytic activities of the examined complexes are in the range 1860 – 3798 g∙mmol-1∙h-1∙bar-1. [ABSTRACT FROM AUTHOR]

This report presents the structure of the 5-aminopyridine-2-carboxylate chromium(III) complex. The thermodynamic stability of the title complex has been examined. The conductometric titration confirmed the stoichiometry of the chromium(III) complex. New complex is highly active catalyst in the oligomerization reaction of 2-chloro-2-propen-1-ol. • Crystal structure of new 5-aminopyridine-2-carboxylate complex has been determined. • Thermodynamic stability of the title complex in aqueous solution has been examined. • New 5-aminopyridine-2-carboxylate complex has been characterized as a precatalyst. This publication presents a new chromium(III) complex with 5-aminopyridine-2-carboxylate anions. The title compound was characterized by single-crystal X-ray diffraction analysis, potentiometric and conductometric titrations. The oligomerization reaction of the 2-chloro-2-propen-1-ol alcohol was carried out using the title complex as a catalyst for the reaction. The resulting product was examined by MALDI-TOF MS and infrared spectroscopy. The catalytic activity of the complex in the oligomerization reaction of 2-chloro-2-propen-1-ol was determined. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new complex [VO (tda) ] · 0.5 H 2 O has been synthesized and analysed. • Polycarboxylate complex compounds were used in the oligomerization of ethylene. • The catalytic activities of the compounds were calculated and compared. • [Co(ida)(bipy)]·4 H 2 O showed the highest Ca (<1500 g∙mmol−1·h−1·bar−1). • The type of main and auxiliary ligand influence on the catalytic activity. The polymerization and oligomerization of olefins, especially ethylene, is a process of great industrial and scientific importance in polymer chemistry. Catalysts are an essential part of this reaction, and a new report of a catalyst improving this process is worthy of special attention. During this study, nine complex compounds based on oxovanadium(IV) and cobalt(II) ions in combination with organic ligands, e.g., dipicolinic acid, 2,2′-bipyridine, iminodiacetic acid, diglycolic acid, thiodiacetic acid, 1,10-phenanthroline were synthesized. The compound [VO(tda) · 0.5 H 2 O] is a new complex not previously reported in the literature, and its synthesis and structure are described in this article. The high catalytic activity values in other oligomerization processes in other olefins led us to use the synthesized compounds as precatalysts in the oligomerization reaction. Subsequently, their catalytic activity was also calculated in this process. The obtained oligomerization products were then analyzed by IR, MALDI-TOF-MS, TG, DSC, and SEM techniques to characterize the obtained products and verify the correctness of the oligomerization reaction. Based on the obtained data, the catalytic activity values were compared and the most active catalyst was selected. The best catalyst was a cobalt(II) compound containing an iminodiacetic acid anion and 2,2′-bipyridine in its structure. However, all complexes can be classified as highly active and active catalysts for ethylene oligomerization. The presented studies show novel catalysts that have in their structure other metal ions than those most commonly used in the literature so far. Additionally, coordination compounds of this type have not been previously used in ethylene oligomerization. Moreover, these studies are a source of knowledge on the correlation between catalyst structure and catalytic activity value, thanks to which they provide essential information necessary for the design of next-generation catalysts used for ethylene oligomerization and polymerization. [ABSTRACT FROM AUTHOR]

• [Cr(dipic)(H 2 O) 3 ]Cl ⋅ 2 H 2 O is the highly active catalyst. • The oligomers have been characterized by NMR, IR and MALDI-TOF-MS. • The oligomerization undergoes at atmospheric pressure and at the room temperature. A new chromium(III) complex with dipicolinate anion i.e. [Cr(dipic)(H 2 O) 3 ]Cl ⋅ 2 H 2 O and its crystal structure, the physicochemical properties and catalytic activity for the oligomerization reaction of 2-chloro-2-propen-1-ol is presented in this report. The X-ray analysis of the new chromium(III) complex has been performed and based on the X-Ray analysis the crystallographic parameters have been determined. Conductivity titrations have been performed to determine the stoichiometry of the complex in aqueous solutions. The stability of the titled compound in aqueous solutions has been examined by potentiometric titrations. The nitro blue tetrazolium test has been carried out to check the antioxidant properties of [Cr(dipic)(H 2 O) 3 ]Cl ⋅ 2 H 2 O. The oligomerization reaction of 2-chloro-2-propen-1-ol alcohol catalyzed by the titled chromium(III) complex has been conducted. The catalytic activity of [Cr(dipic)(H 2 O) 3 ]Cl ⋅ 2 H 2 O has been calculated. The oligomerization products have been characterized using the nuclear magnetic resonance spectroscopy, the matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry and the infrared spectroscopy. [ABSTRACT FROM AUTHOR]

The oxydiacetate and iminodiacetate complexes of VO(IV) with bipy and phen are high active catalysts for the formation process of poly(2-chloroallyl alcohol) oligomers. The products obtained as the results of the oligomerization reactions after the use of catalysts undergo the thermal decomposition in the similar way. • New highly active catalysts of 2-chloro-2-propen-1-ol oligomerization were studied. • The catalytic activities are in the range 358.97–1004.70 g·mmol−1·h−1. • The oligomers thermally decompose releasing H 2 O, CO 2 , CO and HCl. • The oxydiacetate and iminodiacetate complexes of oxidovanadium(IV) are catalysts. • The oligomerization undergoes at room temperature and under atmospheric pressure. The oxydiacetate (oda) and iminodiacetate (ida) complexes of oxidovanadium(IV) with 1,10-phenantroline (phen) and 2,2′-bipyridine (bipy) have been synthesized. The six following complexes: [VO(oda)(H 2 O) 2 ], [VO(oda)(bipy)]·2H 2 O, [VO(oda)(phen)]·1.5H 2 O, [VO(ida)(H 2 O)]·H 2 O, [VO(ida)(bipy)]·2H 2 O and [VO(ida)(phen)]·2H 2 O have been used as the new catalysts for the oligomerization of 2-chloro-2-propen-1-ol. The oligomerization process undergoes very easy at room temperature and under atmospheric pressure. All products of the oligomerizations have been studied with the several analytical methods such as the matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF-MS), the nuclear magnetic resonance spectroscopy (NMR) and the thermogravimetric analysis (TGA) coupled with the analyzer of the infrared (IR) spectroscopy. The catalytic activities of the synthesized oxidovanadium(IV) complexes have been calculated which show that these complexes are the active catalysts in the 2-chloro-2-propen-1-ol oligomerization. [ABSTRACT FROM AUTHOR]

The iminodiacetate cobalt(II) complex is a new highly active catalyst for the 2-chloro-2-propen-1-ol oligomerization. The antioxidant activity of [Co(ida)(H 2 O) 2 ] against superoxide anion radical has been confirmed. It is very interesting to note that the NBT test results have shown that the tested complex is a stronger antioxidant than l -ascorbic acid. A coordination complex, [Co(ida)(H 2 O) 2 ] where ida denotes iminodiacetate, as a potential highly active catalyst was designed and obtained. To obtain a full structural characteristic, i.e. to determine the crystallographic details and the spatial structure of the crystals of the studied complex, X-ray analysis was carried out. [Co(ida)(H 2 O) 2 ] was investigated also by elementary analysis, IR spectrophotometry and MALDI-TOF-MS to get a full physicochemical characteristics. The stoichiometry of [Co(ida)(H 2 O) 2 ] in aqueous solutions was determined using the conductometric titrations. Consequently, the potentiometric titrations were performed to determine the thermodynamic stability of the title compound in aqueous solutions. Moreover, the antioxidant activity of [Co(ida)(H 2 O) 2 ] against superoxide anion radical has been examined by NBT test. The catalytic properties of the cobalt(II) complex, [Co(ida)(H 2 O) 2 ], were examined. It turned out that complex studied is a highly active catalyst for the 2-chloro-2-propen-1-ol oligomerization. It catalyzes the reaction of oligomerization in mild conditions: under normal pressure and at room temperature. The oligomerization reaction products were fully characterized by the following spectroscopic methods: IR, NMR, MALDI-TOF-MS. Furthermore, to investigate the thermal behavior of the obtained oligomer, the product of the oligomerization obtained using [Co(ida)(H 2 O) 2 ] as the catalyst was studied with the use of thermal analysis methods, i.e. DSC and TG. The catalytic activity of the title complex has also been calculated. [ABSTRACT FROM AUTHOR]