Synthesis of Tris(arylphosphite)-ligated Cobalt(0) Complexes [Co2(CO)6{P(OAr)3}2], and their Reactivity towards Phenylacetylene and Diphenylacetylene
Abstract
1428 7979
Synthesis of Tris(arylphosphite)-ligated Cobalt(0) Complexes [Co2(CO)6{P(OAr)3}2], and their Reactivity towards Phenylacetylene and DiphenylacetyleneAbstract
The dinuclear complexes [Co2(CO)6{P(OAr)3}2] (1a, Ar = Ph; 1b, Ar = o-Tol) were prepared and reacted with PhC≡CH and PhC≡CPh to yield dimetallatetrahedranes [{(ArO)3P}(OC)2Co-Co(μ-RC≡CPh)(CO)2{P(OAr)3}] (3a, Ar = Ph, R = H; 3b, Ar = o-Tol, R = H; 3c, Ar = Ph, R = Ph; 3d, Ar = o-Tol, R = Ph). The main reaction of diphenylacetylene was accompanied by a side reaction, leading to the dissociation of a P(OAr)3 ligand for the formation of mono(phosphite) complexes [{(ArO)3P}(OC)2Co-Co(μ-PhC≡CPh)(CO)3] (2b, R = Ph; 2d, R [...] 1428 7979 |
The Unexpected Synthesis of a New (μ2-hydroxo-μ2-peroxo) Dicobalt Complexby
Yashiro Rojas
,
Evana Halaka
,
Mary Hanna
,
Alex Sidotu
,
Jehan Joma
,
Mina Mikhael
,
Roger A. Lalancette
and
Ivan Bernal
Abstract
The compound, [cis-dichloro-(tris-2-amino(ethylamine))cobalt(III)]chloride hydrate, [cis-Cl2-(tren)Co(III)Cl]·H2O, a conglomerate crystallizing in P21 with Z = 4 (Z’ = 2), has been used as a precursor in the synthesis of a new dicobalt(III) peroxo complex: [(μ2-hydroxo)(μ2-peroxo)bis(tris-2-amino(ethylamine))di-cobalt(III)] tris(triiodide) dihydrate. This material crystallizes, without disorder, in space group P212121 with Z = 4 (Z’ = 2), thus making it, unambiguously, an example of a conglomerate. Its cell constan [...] 1374 7099 |
1-Decylbenzimidazole Copper(II) Complexes: Combined Experimental and DFT PCM and TD-DFT Computational StudiesAbstract
1-Decylbenzimidazole (dbim) copper(II) complexes formed during solvent extraction were thoroughly studied, and their structures were predicted. Density functional theory (DFT) calculations of their structures and Time-dependent DFT (TD-DFT) calculations of their spectra indicated that 1-decylbenzimidazole forms both mono- and binuclear complexes with copper(II), with coordination numbers of 4 or 5. At the molar ratio of [Cu(II)]aq/[dbim]org ≥ 1 and at [Cl-]aq ≥ 0.9 mol dm-3 in the extraction media, a binuclear 1:1 [...] 1327 7344 |
A Preparation and Structural Characterization of the Hydrated Trifluoride Salt of the [Co(NH3)6]3+ Cation: [Co(NH3)6]F3 · 2H2O. The Unexpected Preparation of [Co(NH3)6](BF4)(SiF6) from Pyrex Glass, and the Syntheses and Structures of (NH4)[Co(NH3)6](BF4)2(2Cl) and of (NH4)[Co(NH3)6]2(SiF6)3(Cl) · 3H2OAbstract
It is historically interesting to note that, whereas the [Co(NH3)6]3+ cation was isolated by Tassaert in 1798 (which he described as the tri-chloride) and that, in the early days of Coordination Chemistry, Jørgensen and Werner isolated many of its other salts, the fluoride was never reported. In fact, in relatively modern times, lack of success was, invariably, the result of attempting its isolation and full characterization. Significantly, there is no entry for its structure in standard sources such as Inorganic C [...] 1260 8020 |
A Methodology to Estimate Net Proton: Phosphorus Co-Adsorption Ratios for Acidic SoilsAbstract
Despite extensive research, the behaviour of the key nutrient element, phosphorus (P), in soil is not yet fully understood. This study focussed on the outstanding issue of the co-adsorption of protons (H+) and P by soils. We developed a congruent set of measures to determine the net H+:P co-adsorption ratio and tested it on goethite, for which a ratio of 1.6:1 had been estimated under CO2-free conditions for additions of NaH2PO4. Under our conditions, and using additions of KH2PO4, the net H+:P co-adsorption ratio [...] 1321 8403 |
An Estimate of Possible Impacts of Superoxide Chemistry on Seawater pH: A Mapping ExerciseAbstract
Superoxide, produced photochemically as well as microbially, is an important reactant present in seawater and a major source of hydrogen peroxide. Superoxide decay may occur through catalyzed or uncatalyzed dismutation forming H2O2 and O2, through oxidation to O2, or through reduction into H2O2. Under definite circumstances, the redox processes that are different from dismutation could produce or consume H+, thereby altering the pH of seawater. In order to alter the pH, these processes have to involve, together wit [...] 1168 7150 |
Personal Observations on the Critical and Unusual Role of Palladium Environment on Reaction PathwaysAbstract
This article summarizes some surprising palladoreactions occurring in a transition metal environment, discovered by our team, and the proposed corresponding mechanisms. 1183 7599 |
Vanadium: Biological, Environmental, and Engineering AspectsAbstract
Vanadium is an element that is widely distributed in Earth’s crust as well as in sea-water and ground-water reservoirs. Therefore, it exerts a great influence on the issues related to life and environment. Vanadium is utilized by several marine organisms. For example, there are vanadate-dependent haloperoxidases in algae and several bacteria, e.g., Azotobacter, use it for nitrogen fixation and bacterial reduction involves the conversion of vanadate to oxidovanadium (IV). The similarity between vanadate and phosphat [...] 1491 9407 |
Solvatochromism of Copper(II) Complexes Derived from Trifluoroacetylacetone and Dinitrogen LigandsAbstract
Mixed ligand copper(II) complexes of the empirical formula [Cu (L)(TFAA)]X, where L represents 2,2´-bipyridine (Bipy), 1,10´-phenanthroline (Phen), or 4,7-diphenyl-1,10´- phenanthroline (Dphen), TFAA is 1,1,1-Trifluoro-2,4-pentanedione, and X is the counter ion (BF4- or ClO4-), were synthesized and characterized by spectroscopic, magnetic, molar conductance, elemental, and thermal analysis. Solvatochromic studies revealed that all the complexes showed bathochromic shifts. A square planar geometric structure is prop [...] 1652 9647 |
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