Solid-State Binding Studies of Group 2 Metal Ions with 12-Crown-4Dedicated to Professor Joachim Strähle on the Occasion of his 65thBirthday

Junk, Peter Courtney; Louis, Lance M.; Smith, Matthew K.

doi:10.1002/1521-3749(200206)628:5<1196::aid-zaac1196>3.0.co;2-6

Cited by 20 publications

(6 citation statements)

References 18 publications

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“…The average Ca–O distances of 2.39, 2.36, 2.38, 2.42, and 2.41 Å in 2 , 3 , 4 , 5 , and 7 , respectively, compare well with those of 2.378–2.501 Å in other calcium diethyl ether adducts, − 2.355–2.502 Å in other calcium thf adducts, − ,,− 2.415–2.507 in other calcium dme adducts, ,,, 2.444–2.514 Å in other calcium diglyme complexes, ,, and 2.380–2.55 Å in other calcium 12-crown-4 adducts. − …”

Section: Resultssupporting

confidence: 58%

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

Dunbar

Girolami

2013

Inorg. Chem.

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The reaction of CaBr2 with 2 equiv of sodium N,N-dimethylaminodiboranate, Na(H3BNMe2BH3) in Et2O at 0 °C followed by crystallization and drying in vacuum yields the unsolvated calcium compound Ca(H3BNMe2BH3)2, 1. Before the vacuum drying step, the colorless crystals obtained by crystallization consist of the diethyl ether adduct Ca(H3BNMe2BH3)2(Et2O)2, 2. If the reaction of CaBr2 with 2 equiv of Na(H3BNMe2BH3) is carried out in the more strongly coordinating solvent tetrahydrofuran (thf), the solvate Ca(H3BNMe2BH3)2(thf)2, 3, is obtained. This compound does not desolvate as easily in vacuum as the diethyl ether compound 2. Treating the thf adduct 3 with 1,2-dimethoxyethane (dme), bis(2-methoxyethyl) ether (diglyme), or N,N,N',N'-tetramethylethylenediamine (tmeda) in thf affords the new compounds Ca(H3BNMe2BH3)2(dme), 4, Ca(H3BNMe2BH3)2(diglyme), 5, and Ca(H3BNMe2BH3)2(tmeda), 6, respectively, in greater than 60% yields. Treatment of 3 with 2 equiv of the crown ether 12-crown-4 in thf affords the charge-separated salt [Ca(12-crown-4)2][H3BNMe2BH3]2, 7. Crystal structures of all the Lewis base adducts are described. Compounds 2-6 all possess chelating κ(2)-BH3NMe2BH3-κ(2) groups, in which two hydrogen atoms on each boron center are bound to calcium. Compound 7 is the only ionic compound in the series; the Ca atom is completely encapsulated by two 12-crown-4 rings, and the anions are charge-separated counterions within the unit cell. When heated, the dme, diglyme, and tmeda compounds 4, 5, and 6 melt without decomposition, and can be sublimed readily under reduced pressure (1 Torr) at 90 °C (4) and 120 °C (5, 6). The dme adduct is one of the most volatile calcium compounds known, and is a promising CVD precursor for the growth of calcium-containing thin films.

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Section: Resultssupporting

confidence: 58%

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

Dunbar

Girolami

2013

Inorg. Chem.

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“…There are a few systems where crystallographic data exist for the same ligand associated with different metal ions. For example, Smith 71 studied the complexes formed between some of the second row metals and 12-crown-4. He found that while the O-Sr 2+ -O angle in the crown ether complex was 62.61, that of O-Ca 2+ -O was 65.81.…”

Section: Resultsmentioning

confidence: 99%

The effect of surface attachment on ligand binding: studying the association of Mg²⁺, Ca²⁺and Sr²⁺by 1-thioglycerol and 1,4-dithiothreitol monolayers

Burshtain

Mandler

2006

Phys. Chem. Chem. Phys.

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The difference in the heterogeneous binding of Mg(2+), Ca(2+) and Sr(2+) ions by 1-thioglycerol (TG) and 1,4-dithiothreitol (DTT) spontaneously adsorbed monolayers on Au has been studied following the changes in the double layer capacity. A mathematical treatment, based on calculating the electrochemical potential difference at the monolayer-electrolyte interface, has followed our recent work which dealt with the acid-base equilibrium at the interface as a means of calculating the pK of ionizable SAMs and their binding with Cd(2+). Experimentally, spontaneously adsorbed monolayers of TG and DTT were assembled on Au surfaces and studied by impedance spectroscopy and alternating current voltammetry (ACV). The capacity was measured for each of the modified surfaces at increasing concentrations of the divalent metal ions separately. The goal of this study has been to examine the effect of metal ion binding by similar ligands that are differently attached onto the surface. TG and DTT monolayers differ in their flexibility, which is a result of their attachment to the surface through one and two arms, respectively. The general trend of the apparent heterogeneous association constants of the divalent metal ions, which were calculated from the capacity measurements, was substantially different from the classical Irving-Williams series that is applicable to homogeneous systems. This difference could be nicely explained by the reduction of the degree of freedom and flexibility of the attached ligands.

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“…A previously published divalent europium structure ([Eu(12c4)(OH 2 ) 3 Cl]Cl), 22 while not entirely analogous to the trans halide half-sandwich motif, was measured via single-crystal X-ray diffraction at both room temperature and 100 K and is included in Table S11. The metal oxygen bond lengths and distance between the metal and the 12-crown-4 cavity centroid for Ln(12c4)(THF) 2 I 2 are dramatically longer than those of [Ln(12c4)(Cl) 2 (OH 2 ) 2 ]Cl (Ln = Ho−Lu), 18 comparable to that of [Eu(12c4)(Cl)-(OH 2 ) 3 ][Cl], 22 and smaller than [Ba(12c4)(X) 2 (OH 2 )] (X − = Br − , I − ), 28 as would be expected based on the trends in the metals' ionic radii.…”

Section: ■ Materials and Methodsmentioning

confidence: 99%

Coordination Chemistry and Spectroscopic Properties of Eu(II), Sm(II), and Yb(II) with 12-Crown-4

Wineinger,

Scheibe,

Brannon

et al. 2024

Crystal Growth & Design

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The coordinative properties of 12-crown-4 (12c4) with Sm 2+ , Eu 2+ , and Yb 2+ have been examined using nonaqueous and inert atmosphere conditions and led to the isolation of five complexes: Ln( 12c4)(THF) 2 I 2 (Ln = Sm 1, Eu 2), [Ln(12c4) 2 (CH 3 CN)][Ph 4 B] 2 (Ln = Sm 3, Eu 4), and [Yb(12c4) 2 ][Ph 4 B] 2 (5). Most complexes were prepared via the salt metathesis of LnI 2 with tetrabutylammonium tetraphenylborate ([TBA][Ph 4 B]) and 12-crown-4 in acetonitrile, while some were crystallized from THF. The half-sandwich compounds 1 and 2 crystallize with trans iodide orientation and exhibit mixed d−f and f−f and d−f photoluminescence when excited with 546 and 365 nm light, respectively. The full sandwich compounds 3 and 4 feature [Ln( 12c4) 2 (CH 3 CN)] 2+ complex cations, where two 12c4 molecules are not sufficiently large to coordinatively saturate these larger cations without further ligation, while the smaller Yb 2+ cation is fully encapsulated in two 12c4 molecules (5). Solution UV−vis−NIR studies show that when 12c4 is added to acetonitrile solutions of LnI 2 , the f−d transitions shift to higher energies, suggesting destabilization of the lower lying d orbitals and increased stability of the divalent state by complexation to 12c4 in solution.

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Solid-State Binding Studies of Group 2 Metal Ions with 12-Crown-4Dedicated to Professor Joachim Strähle on the Occasion of his 65thBirthday

Cited by 20 publications

References 18 publications

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

The effect of surface attachment on ligand binding: studying the association of Mg²⁺, Ca²⁺and Sr²⁺by 1-thioglycerol and 1,4-dithiothreitol monolayers

Coordination Chemistry and Spectroscopic Properties of Eu(II), Sm(II), and Yb(II) with 12-Crown-4

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Solid-State Binding Studies of Group 2 Metal Ions with 12-Crown-4Dedicated to Professor Joachim Strähle on the Occasion of his 65thBirthday

Cited by 20 publications

References 18 publications

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

Synthesis and Characterization of Calcium N,N-Dimethylaminodiboranates as Possible Chemical Vapor Deposition Precursors

The effect of surface attachment on ligand binding: studying the association of Mg2+, Ca2+and Sr2+by 1-thioglycerol and 1,4-dithiothreitol monolayers

Coordination Chemistry and Spectroscopic Properties of Eu(II), Sm(II), and Yb(II) with 12-Crown-4

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The effect of surface attachment on ligand binding: studying the association of Mg²⁺, Ca²⁺and Sr²⁺by 1-thioglycerol and 1,4-dithiothreitol monolayers