Anionic polymerization of polar monomers. I. Ultraviolet-visible spectroscopic and conductometric studies of ion pairs of alkali salts of vinyl 2-, 3-, and 4-pyridine-type carbanions and their crown ether complexes in aprotic media

1975 ◽  
Vol 97 (10) ◽  
pp. 2805-2810 ◽  
Author(s):  
C. J. Chang ◽  
R. F. Kiesel ◽  
T. E. Hogen-Esch
Keyword(s):  
Crown Ether ◽  
Anionic Polymerization ◽  
Ion Pairs ◽  
Crown Ether Complexes ◽  
Polar Monomers ◽  
Alkali Salts

Synthesen und Kristallstrukturen der Kronenether-Komplexe (18-Krone-6) · 2CH3CN, [Na-15-Krone-5][ReO4] · CH3CN und [Na-15-Krone-5]PF6 / Syntheses and Crystal Structures of the Crown Ether Complexes (18-Crown-6) · 2 CH3CN, [Na-15-Crown-5][ReO4] · CH3CN, and [Na-15-Crown-5]PF6

1989 ◽  
Vol 44 (12) ◽  
pp. 1524-1530 ◽  
Author(s):  
Frank Weller ◽  
Harald Borgholte ◽  
Harald Stenger ◽  
Stefan Vogler ◽  
Kurt Dehnicke
Keyword(s):  
Crown Ether ◽  
Sodium Fluoride ◽  
Ion Pairs ◽  
Sodium Atom ◽  
Acetonitrile Solution ◽  
Space Group ◽  
Crown Ether Complexes ◽  
Water Space ◽  
Ether Molecule ◽  
Oxygen Atoms

Single crystals of (18-crown-6) · 2 CH3CN were obtained by cooling a solution of 18-crown-6 in acetonitrile to 4 °C. Space group P21/n, Z = 2, 629 observed independent reflexions, R = 0.062. Lattice dimensions at 19°C: a = 911.7(1), b = 852.0(1), c = 1370.0(2) pm; β = 104.61(1)°. The compound forms a molecular structure with approximate D3d symmetry of the crown ether molecule, and C—H ··· O interactions of the acetonitrile molecules with the crown ether, the Η···Ο distances being 243, 253, and 267 pm, respectively.[Na-15-crown-5][ReO4] · CH3CN is formed as a by-product of the reaction of ReNCl4 with sodium fluoride in acetonitrile in the presence of 15-crown-5 and traces of water. Space group Ρ 1̄ , Ζ = 2, 3107 observed independent reflexions, R = 0.045. Lattice dimensions at 19°C: a = 823.4(1), b = 1078.8(1), c = 1204.0(1) pm; α = 112.40(1)°, β = 94.35(1)°, γ = 104.63(1)°. The compound forms ion pairs, in which the sodium atom is sixfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by one oxygen atom of the ReO4- ion, which is only slightly distorted. The bond length Na—OReO3 is 237.8(8) pm, the bond angle NaORe is 164.3(5)°.[Na-15-crown-5]PF6 is formed in the reaction of [ReCl3(NSCl)2 · POC13] with sodium fluoride in acetonitrile solution in the presence of 15-crown-5. Space group Pna21, Ζ = 4, 1130 observed independent reflexions, R = 0.123. The high R value is due to disorder of the skeletal atoms of the crown ether molecule. The compound forms ion pairs, in which the sodium atom is sevenfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by two fluorine atoms of the PF6- ion with Na—F bond lengths of 240(2), and 246(2) pm, respectively.

Synthesen und Kristallstrukturen der Kronenether-Komplexe [Li3(12-Krone-4)3O2CCH3] [Cd(Se4)2], {[K(18-Krone-6)]2[Hg(Se4)2]}2 und [Na(15-Krone-5)]NO3 / Syntheses and Crystal Structures of the Crown Ether Complexes [Li3(12-Crown-4)33O2CCH3][Cd(Se4)2], {[K(18-Crown-6)]2[Hg(Se4)2]}2, and [Na(15-Crown-5)]NO3

1989 ◽  
Vol 44 (4) ◽  
pp. 444-454 ◽  
Author(s):  
Gertrud Kräuter ◽  
Frank Weller ◽  
Kurt Dehnicke
Keyword(s):  
Crown Ether ◽  
Ion Pairs ◽  
Sodium Atom ◽  
Ethanolic Solution ◽  
Lithium Ions ◽  
Space Group ◽  
Crown Ether Complexes ◽  
Structure Determinations ◽  
Centrosymmetric Dimers ◽  
Oxygen Atoms

[Li3(12-crown-4)3O2CCH3][Cd(Se4)2] has been prepared by the reaction of [Li(12-crown-4)]2Se6 with Cd(C2CCH3)2 in ethanolic solution. The corresponding polyselenide complex of mercury is formed by the reaction of [K(18-crown-6)]2Se6 with Hg(O2CCH3)2 in the same solvent. Both com pounds form dark red crystals, which were characterized by single crystal X-ray structure determinations. The only product to be isolated from the reaction of Bi(NO3)3·5H2O with [Na( 15-crown-5)]2Se6 in ethanolic solution was [Na(15-crown-5)]NO3, whose structure has also been determined. [Li3(12-crown-4)3O2CCH3][Cd(Se4)2]: space group Pbca, Z = 8. 1404 observed independent reflexions. R = 0.097. Lattice dimensions (19 °C): a = 1981.5(6). b = 1400.3( 1), c = 3268.9(9) pm. The compound forms a dicationic ensemble, in which three lithium ions coordinate with the oxygen atoms of the acetate ion. In the anions the cadmium atom is coordinated tetrahedrally by four selenium atoms of two Se42- units.{[K (18-crown-6)]2[Hg(Se4)2]}2: space group P 1, Z = 1. 3210 observed independent reflexions, r = 0.055. Lattice dimensions (19 °C): a = 1057.4(2). b = 1130.6(2), c = 2000.1(2) pm. α = 88.52(1)°, β = 85.86(1)°, γ = 66.22(1)°. The com pound has a complex ionic structure, in which the formula units form centrosymmetric dimers through K-O contacts between two cations. In addition there are K···Se contacts with the spiro-bicyclic anions, which - together with 6 K-O bonds within the crowns - lead to the coordination number of 8 for the remaining potassium ions.[Na(15-crown-5)]NO3: space group P212121, Z = 4. 1211 observed independent reflexions. R = 0.052. Lattice dimensions (20 °C): a = 912.9(2). b = 989.6(1). c = 1658.3(3) pm. The compound forms ion pairs, in which the sodium atom coordinates with the five oxygen atoms oi the crown ether, as well as with two oxygen atoms of the nitrate ion with Na -O bond lengths of 240 and 247 pm.

Synthesis, Characterization, and Reaction of Crown Ether Complexes of Aqua(hydroxy)(aryl)iodonium Ions

2005 ◽  
Vol 44 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Masahito Ochiai ◽  
Kazunori Miyamoto ◽  
Yukie Yokota ◽  
Takashi Suefuji ◽  
Motoo Shiro
Keyword(s):  
Crown Ether ◽  
Crown Ether Complexes
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