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Among the inorganic compounds, there are many influential crystalline structures, and magnesium iodide is the most selective. In the making of medicine and its development, magnesium iodide is considered a multipurpose and rich compound. Chemical structures and networks can be studied by given tools of molecular graph theory. Given tools of molecular graph theory can be studied for chemical structures and networks, which are considered economical with simple methodology. Edge weight-based entropy is a recent advent tool of molecular graph theory to study chemical networks and structures. It provides the structural information of chemical networks or their related build-up graphs and highlights the molecular properties in the form of a polynomial function. In this work, we provide the edge weight-based entropy of magnesium iodide structure and compute different entropies, such as Zagreb and atom bond connectivity entropies.

Reaction of a lithium boryl, [(THF)2 Li{B(DAB)}] (DAB=[(DipNCH)2 ]2- , Dip=2,6-diisopropylphenyl), with a dinuclear magnesium(I) compound [{(Mes Nacnac)Mg}2 ] (Mes Nacnac=[HC(MeCNMes)2 ]- , Mes=mesityl) unexpectedly afforded a rare example of a terminal magnesium boryl species, [(Mes Nacnac)(THF)Mg{B(DAB)}]. Attempts to prepare the magnesium boryl via a salt metathesis reaction between the lithium boryl and a β-diketiminato magnesium iodide compound, instead led to an intractable mixture of products. Similarly, reaction of the lithium boryl with a β-diketiminato beryllium bromide precursor, [(Dep Nacnac)BeBr] (Dep=2,6-diethylphenyl) did not give a beryllium boryl, but instead afforded an unprecedented example of a beryllium substituted diazaborole heterocycle, [{(Dep Nacnac)Be(4-DAB-H )}BBr]. For sake of comparison, the same group 2 halide precursor compounds were treated with a potassium gallyl analogue of the lithium boryl, viz. [(tmeda)K{:Ga(DAB)}] (tmeda=N,N,N',N'-tetramethylethylenediamine), but no reactions were observed.

A concise protocol for anti-hydromagnesiation of aryl alkynes was established using 1 : 1 molar combination of sodium hydride (NaH) and magnesium iodide (MgI2) without the aid of any transition metal catalysts. The resulting alkenylmagnesium intermediates could be trapped with a series of electrophiles, thus providing facile accesses to stereochemically well-defined functionalized alkenes. Mechanistic studies by experimental and theoretical approaches imply that polar hydride addition from magnesium hydride (MgH2) is responsible for the process., Anti-hydromagnesiation of aryl alkynes was facilitated solely by magnesium hydride. The resulting alkenylmagnesium intermediates were functionalized with various electrophiles to afford stereochemically defined tri-substituted alkenes.

Graph theory, which has become a powerful area of mathematics, owns much advancement in the field of mathematical chemistry. Recently, chemical graph theory has turned into a very popular area among researchers because of its wide-ranging applications in the field of mathematical chemistry. The manipulation and inspection of chemical structural information is made feasible using molecular descriptors. The molecular topological descriptors are the numerical invariants of a molecular graph and are valuable for predicting their bioactivity. An abundant variety of such indices are taken into consideration and used in pharmaceutical researchers, in theoretical chemistry, in drugs and in several other fields. A topological index actually relates a chemical structure by means of a numeric number. In this recent research work, we have considered the chemical graph of magnesium iodide. We computed degree based topological indices. Mainly, we addressed atom-bond connectivity index (ABC), geometric arithmetic index (GA), fourth atom-bond connectivity index (ABC4), The fifth geometric-arithmetic index (GA5), general Randic' index Ra(G) and First Zagreb index M1(G), Second Zagreb index M2(G) for magnesium iodide, MgI2. Furthermore, the results are analysed and we have provided general formulas for all these above mentioned families of graphs that are in fact very helpful in studying the underlying topologies.

A protocol for regio-controlled hydromagnesiation of 1,3-enynes was developed using magnesium hydride that is generated in situ by solvothermal treatment of sodium hydride (NaH) and magnesium iodide (MgI2 ) in THF. The resulting allenylmagnesium species could be converted into tri- and tetra-substituted allenes by subsequent treatment with various carbon- and silicon-based electrophiles with the aid of CuCN as a catalyst. Ministry of Education (MOE) Nanyang Technological University Accepted version This work was supported by funding from Nanyang Technological University (NTU) (for S.C.) and the Singapore Ministry of Education (Academic Research Fund Tier 2: MOE2019-T2-1-089 for S.C.) as well as JSPS KAKENHI grant JP19K06992 (for R.T.) and the Naito Foundation (for R.T.).

A library of ten dinucleating bis(amidine) and bis(guanidine) ligands, in which the bridging groups, terminal rests, and backbone substituents were systematically altered, has been synthesized and subsequently applied in metallation reactions using three different magnesium sources. Eight Mg complexes could be isolated and fully characterized, and in seven cases their solid-state structure could be determined by means of single crystal X-ray diffraction analysis. The results evidence a versatile coordination behaviour, which ranges from the first dinuclear heteroleptic magnesium iodide complex to dinuclear homoleptic complexes. These findings indicate the crucial impact of both the ligand and the magnesium source not only on the accessibility of well-defined dinuclear complexes but also on the aggregation in solution and in the solid state.

The application of amine derivatives as coupling partners is rare due to the inherent strength of the C-N bond. Herein, we report the first cross-electrophile coupling reaction of unstrained benzylic sulfonamides. Nickel-catalyzed intramolecular cross-electrophile coupling reactions of acyclic and cyclic benzylic sulfonamides with pendant alkyl chlorides generate cyclopropane products. Mechanistic experiments and DFT calculations are consistent with initiation of the reaction by magnesium iodide accelerated oxidative addition of the benzylic sulfonamide. This work establishes neutral and unstrained amine derivatives as XEC partners, furnishes structural rearrangement of benzylic sulfonamides, and provides valuable information regarding catalyst design for the development of new cross-electrophile coupling reactions of carbon-heteroatom bonds.

Despite the high efficiency of MAPbI3 perovskite solar cells, the long term stability and degradation in humid atmosphere are issues that still needed to be addressed. In this work, magnesium iodide (MgI2) was first successfully used as a dopant into MAPbI3 perovskite prepared in humid air atmosphere. Mg doping decreased the valence band level, which was determined from photoelectron yield spectroscopy. Compared to the pristine MAPbI3 perovskite film, the 1.0% Mg-doped perovskite film showed increased crystal grain size and formation of pinhole-free perovskite film. Performance of the solar cell was increased from 14.2% of the doping-free solar cell to 17.8% of 1.0% Mg-doped device. Moreover, 90% of the original power conversion efficiency was still retained after storage in 30–40% relative humidity for 600 h.

Friedel–Crafts alkylation of indole and its derivatives with a variety of electron-deficient alkenes catalyzed by Mg and Ca salts has been studied. The dependence of the results on the nature of the starting olefins, substituents on indole, and Michael acceptors, as well as on the composition of the Lewis acid is discussed. High yields of the addition products were achieved in the addition of indole to β,γ-unsaturated α-keto esters and coumarin derivatives, some nitroolefins, and arylidenemalonates. Reactions involving arylidenemalonates were found to be the most versatile and smooth, the best yields reached 92%. Among the Mg and Ca salts tested, magnesium iodide (MgI2) proved to be the most appropriate catalyst in the addition to various unsaturated carbonyl compounds, while calcium triflimide [Ca(NTf2)2] efficiently catalyzed the addition to nitroolefins.

The crystal structures of newly obtained [Mg(OC(NH2)2)2(H2O)4]I2 (tetraaqua bis (urea-O) magnesium diiodide), [Mg(OC(NH2)2)4(H2O)2]I2 (diaqua tetra(urea-O) magnesium diiodide) and [Mg(OC(NH2)2)6]I2 . 4OC(NH2)2 (hexa(urea-O) magnesium diiodide tetraureate) are reported. It is found that the studied compounds crystalize in one and the same space group P21/c and exhibit structure isotypical with the corresponding chlorides and bromides. The complexes were characterized by experimental IR spectroscopic and DTA-TG analyses, and DFT/B3LYP free energy and vibrational calculations at molecular level. The observed trans-conformation in the crystaline (MgX6)2+units was supported by calculated larger thermodynamic stability of trans- conformers as compared to cis ones. The inclusion of Urea in Mg2+ complexes was preferred over water in agreement with the calculated exothermic exchange reactions. The comparative IR spectroscopic analysis of urea and the three Mg2+ complexes studied revealed that ν(C = O)U band shift could be an indication of Mg - OU bond formation and its relative strength. The thermal analyses and calculated exchange reaction energies predicted larger stability of the Mg2+ complexes with an increase of the number of the urea (respectively a decrease of water's number in the first coordinating shell) due to formation of specific network of hydrogen bonds.

The sterically bulky Schiff-base ligand 1 (L1H) was treated with CH3MgI in toluene to give the unexpected homoleptic magnesium complex 2 (L1MgL1) in good yield. However, the reaction of sterically more bulky ligand 3 (L2H) with CH3MgI in diethyl ether yielded the desired heteroleptic magnesium iodide 4 [L2MgI(OEt2)], which was further reduced with sodium to produce the Mg–Na heterodimetallic complex 5. The crystal structures of all new magnesium complexes were determined by single-crystal X-ray diffraction. All new magnesium complexes have been investigated as catalysts for the hydrosilylation of ketones with (EtO)3SiH. The study showed that catalytic activity of the Mg–Na dimetallic complex 5 is superior to those of monometallic magnesium complexes 2 and 4 and is applicable to a series of subatrates.

A novel and efficient approach for the synthesis of quinazolines by aerobic photooxidation with an iodine reagent at room temperature is reported. This method uses harmless visible light from compact fluorescent lamps and molecular oxygen as the sole oxidant without the need for a transition-metal catalyst or harsh reaction conditions.

Perovskite solar cells are gaining increasing popularity due to their unprecedented rise in power conversion efficiency. However, concerns over the potential environmental impact of CH3NH3PbI3 are stimulating experimental and theoretical searches for the replacement of lead by nontoxic elements. In this study we explore all homovalent metal ions which could substitute lead in a perovskite halide configuration by performing a systematic combinatorial search over the entire periodic table. Our screening process selects compounds based on two concurrent criteria: the stability of the compound in a perovskite structure and the band gap. Using these search criteria, we are able to reduce the number of possible compounds from 248 to 25, including 15 compounds which have not yet been proposed as semiconductors for optoelectronics. We identify Mg as a potential candidate for partial replacement of Pb and show that the band gap of hypothetical magnesium iodide perovskites is tunable over a range of 0.8 eV via the ...

As a kind of material possessing thermal stability, biocompatibility and degradability, polysilylethers (PSEs) have potential applications. Different catalytic systems have been developed for the synthesis of PSEs. However, the resulted PSEs have similar structure, which is unfavorable for adjusting its properties. We herein synthesized a series of novel PSEs with pendant Si H groups via cobalt-catalyzed selective dehydrocoupling polymerization. Various diols and prochiral silanes are suitable for this method. This novel PSEs could also be obtained via a Co-catalyzed one-pot two-step process. Furthermore, asymmetric dehydrocoupling polymerization was studied and high-Mn PSE was obtained. After the cleavage of PSE by methyl magnesium iodide, chiral silane was obtained with high yield and moderate enantioselectivity.

This Letter proposes a safe, mild, and environmentally benign method for the synthesis of benzimidazoles from aromatic aldehydes and diamines by aerobic photooxidation using irradiation with visible light, a catalytic amount of magnesium iodide, which serves as both a Lewis acid and an oxidant, and molecular oxygen as the terminal oxidant.

(S)-6-(2-Hydroxy-2-methylpropyl)-3-((S)-1-(4-(1-methyl-2-oxo-1,2-dihydropyridin-4-yl)phenyl)ethyl)-6-phenyl-1,3-oxazinan-2-one (1) and (4aR,9aS)-1-(1H-benzo[d]midazole-5-carbonyl)-2,3,4,4a,9,9a-hexahydro-1-H-indeno[2,1-b]pyridine-6-carbonitrile hydrochloride (2) are potent and selective inhibitor of 11β-hydroxysteroid dehydrogenase type 1 enzyme. These 2 drug candidates developed for the treatment of type-2 diabetes were prepared labeled with carbon-13 and carbon-14 to enable drug metabolism, pharmacokinetics, bioanalytical, and other studies. In the carbon-13 synthesis, benzoic-13 C6 acid was converted in 7 steps and in 16% overall yield to [13 C6 ]-(1). Aniline-13 C6 was converted in 7 steps to 1H-benzimidazole-1-2,3,4,5,6-13 C6 -5-carboxylic acid and then coupled to a tricyclic chiral indenopiperidine to afford [13 C6 ]-(2) in 19% overall yield. The carbon-14 labeled (1) was prepared efficiently in 2 radioactive steps in 41% overall yield from an advanced intermediate using carbon-14 labeled methyl magnesium iodide and Suzuki-Miyaura cross coupling via in situ boronate formation. As for the synthesis of [14 C]-(2), 1H-benzimidazole-5-carboxylic-14 C acid was first prepared in 4 steps using potassium cyanide-14 C, then coupled to the chiral indenopiperidine using amide bond formation conditions in 26% overall yield.

Morita–Baylis–Hillman-like tri- and tetra-substituted β-iodoalkene adducts can be efficiently synthesized from activated alkynes and aldehydes utilizing MgI2 in CH2Cl2 in excellent yields (65–96%, 16 examples) under mild reaction conditions. A variety of electronically diverse aldehydes react with several electron-deficient alkynes in this manner. The reactions proceed in 2–16 h room temperature or reflux. Furthermore, a trisubstituted Z-alkene was shown to thermodynamically isomerize upon exposure to MgI2 and heat to obtain the corresponding (E)-alkene adduct as the only observed stereoisomer.

Polymeric gel electrolyte systems have gained great interest in the last few years due to their suitability for the manufacturing of ionic devices, for example, for dye-sensitized solar cells (DSSCs). In this work, the rheological behavior at fixed temperatures and at fixed frequency of complex systems based on polyacrylonitrile (PAN) and plasticizers such as ethylene carbonate (EC) and propylene carbonate (PC) containing tetrahexylammonium (Hex4NI) and magnesium iodide (MgI2) was studied. These results for these PAN-EC-PC gels suggest a structural change of the “strong-to-weak” type at about 60 °C and the beginning of the gel–sol transition at about 75 °C. These transitions occur at higher temperatures for polymer electrolyte gels containing Hex4NI and even higher with MgI2, suggesting the possibility of post-factum treatments of the gels and of the DSSCs to improve their performance. The rheological results suggest that the progressive substitution of Hex4NI with MgI2leads to a significant improvement in the rheological behavior of the PAN-based electrolytic gel due to the decrease of the mobility of the macromolecules and probably to an increase of the interaction between the inorganic ions and the macromolecules. Moreover, when these gels were used in DSSCs, the sample containing 80(Hex4NI)/40(MgI2) showed the best performance considering its rheological and calorimetric behavior as well as energy conversation efficiency and short-circuit current density.

The effect of using a binary iodide salt mixture in N719 dye-sensitized TiO2 solar cells (DSSCs) is investigated. The cells use tetrapropylammonium iodide (Pr4NI) and magnesium iodide (MgI2) in a plasticized polyacrylonitrile gel in glass/FTO/nano-porous TiO2/gel, I-2/Pt/FTO/glass solar cell structure. The salt composition in the gel electrolyte is varied to optimize the efficiency of DSSCs. The DSSCs with MgI2 or Pr4NI as the only iodide salt showed the efficiencies 2.56 and 4.16 %, respectively, under AM 1.5 (100 mW cm(-2)) illumination while the DSSC with mixed cations with 18.4:81.6 MgI2:Pr4NI molar ratio shows the highest efficiency of 5.18 %. Thus the efficiency enhancement, relative to the high efficiency end member is about 25 %. DC polarization measurements establish the predominantly ionic behavior of the electrolytes, and show that the variation of efficiency with salt composition correlates with the change in short circuit photocurrent density (J (sc)), which appears to be governed by the iodide ion conductivity. It is also found that J (sc) correlates with the iodide ion transference number estimated from DC polarization data taken with non-blocking iodine electrodes. This study suggests that binary iodide mixtures may be used to obtain efficiency enhancement in different types of DSSCs based on polymeric, gel, or solvent electrolytes.

New derivatives for acetylenic morpholine were prepared. Acetylenic amine (Npropargyl morpholine 1) was synthesized by the reaction of propargyl bromide with morpholine in aqueous medium. This compound was used as a synthone for hydroxy acetylenic compounds. Compound (1) was converted to the Grignard reagent (2) by the reaction with methyl magnesium iodide. The reaction of the intermediate (2) with different carbonyl compounds afforded hydroxy acetylenic compound (3). Finally, prepared Npropargyl ether morpholino (4a-i) was prepared by the reaction of the hydroxy acetylenic compound with chloro acetanilide, benzyl chloride via willamson reaction. The structure of the synthesized compounds has been elucidated by the available physical and spectral methods.

A novel and efficient approach for the synthesis of quinazolines by aerobic photooxidation with an iodine reagent at room temperature is reported. This method uses harmless visible light from compact fluorescent lamps and molecular oxygen as the sole oxidant without the need for a transition-metal catalyst or harsh reaction conditions.

Rechargeable magnesium batteries have attracted considerable attention because of their potential high energy density and low cost. However, their development has been severely hindered because of the lack of appropriate cathode materials. Here we report a rechargeable magnesium/iodine battery, in which the soluble iodine reacts with Mg2+ to form a soluble intermediate and then an insoluble final product magnesium iodide. The liquid–solid two-phase reaction pathway circumvents solid-state Mg2+ diffusion and ensures a large interfacial reaction area, leading to fast reaction kinetics and high reaction reversibility. As a result, the rechargeable magnesium/iodine battery shows a better rate capability (180 mAh g−1 at 0.5 C and 140 mAh g−1 at 1 C) and a higher energy density (∼400 Wh kg−1) than all other reported rechargeable magnesium batteries using intercalation cathodes. This study demonstrates that the liquid–solid two-phase reaction mechanism is promising in addressing the kinetic limitation of rechargeable magnesium batteries., Rechargeable magnesium batteries suffer from slow solid-state Mg2+ diffusion in the intercalation cathode. Here the authors show magnesium/iodine chemistry in which the liquid–solid two-phase reaction leads to increased rate capabilities by overcoming the sluggish kinetics.

The authors thank the Australian Research Council (C.J.), The U.S. Air Force Asian Office of Aerospace Research and Development (grant FA2386-14-1-4043 (C.J.)), and the Alexander von Humboldt Foundation for an experienced researcher grant (L.M.). A variety of very bulky amido magnesium iodide complexes, LMgI(solvent)0/1 and [LMg(μ-I)(solvent)0/1]2 (L=-N(Ar)(SiR3); Ar=C6H2{C(H)Ph2}2R′-2,6,4; R=Me, Pri, Ph, or OBut; R′=Pri or Me) have been prepared by three synthetic routes. Structurally characterized examples of these materials include the first unsolvated amido magnesium halide complexes, such as [LMg(μ-I)]2 (R=Me, R′=Pri). Reductions of several such complexes with KC8 in the absence of coordinating solvents have afforded the first two-coordinate magnesium(I) dimers, LMg−MgL (R=Me, Pri or Ph; R′=Pri, or Me), in low to good yields. Reductions of two of the precursor complexes in the presence of THF have given the related THF adduct complexes, L(THF)Mg−Mg(THF)L (R=Me; R′=Pri) and LMg−Mg(THF)L (R=Pri; R′=Me) in trace yields. The X-ray crystal structures of all magnesium(I) complexes were obtained. DFT calculations on the unsolvated examples reveal their Mg−Mg bonds to be covalent and of high s-character, while Ph⋅⋅⋅Mg bonding interactions in the compounds were found to be weak at best. Postprint

In the presence of inorganic iodide, the methoxy CO bond in 2-methoxyfurans may be cleaved to afford the corresponding lactonic anion. Due to the presence of an electron-withdrawing group at the 3-position, the alkylation with normal organic iodides occurred at the 3-position highly regioselectively. However, when electron-deficient allylic iodides with an electron-withdrawing group at the 2-position were used the 5-alkylation products were formed as the major products with sodium iodide as the catalyst. With magnesium iodide as the catalyst, the 5-allylation occurred highly regioselectively. As a whole, the 3- vs. 5-alkylation selectivity may be determined by the relative steric hindrance at the 3- and 5-positions and the electronic effect of the allylic iodides. A rationale was proposed.

A new pentaphenyl liquid crystalline (LC) compounds with 2,3-difluorobenzene moiety exhibiting wide nematic range have been prepared. The key stage is the condensation of the corresponding 3-dimethylaminopropanoyl-4-pentyl benzene hydrochloride with substituted methyl benzyl ketone in the presence of base leading to 3,6-disubstituted cyclohexenones. Methylation with methyl magnesium iodide followed by oxidative aromatization gives three-ring bromides, which are used in the Suzuki cross-coupling reaction. Pentaphenyl LC compounds possessing lateral methyl group have moderate melting points, improved solubility, and miscibility with another LC components. The new compounds could be useful in LC compositions with the high optical anisotropy.

A novel magnesium iodide mediated unusual dimerization–spirocyclopropanation of bromo isomerised Morita–Baylis–Hillman adducts of isatin afforded highly functionalized 3-spirocyclopropane-2-oxindole derivatives as regioisomers in good combined yield. It has been observed that the regioselectivity is dependent on the nature of electron withdrawing group at the activated position. A plausible mechanism involving organomagnesium reagent has been proposed.

Stellatin (3,4-dihydro-8-hydroxy-7-hydroxymethyl-6-methoxyisocoumarin) (8), an extrolite of fungal genera Emericella and Aspergillus, was synthesized. Thus, Vilsmeier-Haack formylation of methyl ester of 3,5-dimethoxy-4-methylphenylacetic acid (1) to afford the formyl ester (2) followed sulfamic acid-sodium chlorite oxidation of the aldehydic function to yield the carboxy ester (3). Chemoselective reduction of ester function in the latter using NaBH(4)/THF/MeOH furnished the corresponding hydroxy acid (4) that on cyclodehydration afforded the 3,4-dihydro-6,8-dimethoxy-7-methylisocoumarin (5). Benzylic bromination of the C-7 methyl in 5 using NBS/benzoyl peroxide to give the 7-bromomethyldihydroisocoumarin (6) followed the nucleophilic substitution using aqueous acetone to provide 7-hydroxymethyl-dihydroisocoumarin (7). Finally, the regioselective demethylation of 8-methoxyl group using anhydrous magnesium iodide furnished the stellatin (8). The dihydroisocoumarins (5-8) were screened for cytotoxic activity against human keratinocyte cell line and were found to exhibit moderate to good activity.

Clauson–Kass reaction of various substituted aniline, primary aryl amide, and sufonyl amide with 2,5-dimethoxytetrahydrofuran was realized in the presence of 10 mol % of MgI2 etherate in a mild, efficient, and highly chemoselective manner. Iodide counterion and solvents (i.e., MeCN) played the critical roles for the unique reactivity of this catalytic system.

Using a mechanochemical technique in the composition range 0 ≤ x (mol.%) ≤ 30 and subsequent heat treatment, (100 − x)(0.6MgS·0.4P2S5) · xMgI2 glasses and glass-ceramics were prepared from 60MgS · 40P2S5 (mol.%) glass and MgI2 crystal. The effects of the addition of MgI2 on the structures and properties of the glass and glass-ceramic electrolytes were examined. The Raman spectra of all the glass-ceramics showed that the glass-ceramics included P2S64 − ions. The glass-ceramic having composition of x = 20 showed electrical conductivity of 2.1 × 10− 7 S cm− 1 at 200 °C.