Octahedral cobalt(III) complexes in dipolar aprotic solvents. XII. Ion association studies in N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide by conductance measurements

1967 ◽  
Vol 89 (26) ◽  
pp. 6858-6864 ◽  
Author(s):  
W. A. Millen ◽  
Donald W. Watts
Keyword(s):  
Dimethyl Sulfoxide ◽  
Association Studies ◽  
Ion Association ◽  
Aprotic Solvents ◽  
Dipolar Aprotic Solvents

Solvation of the halide anions in dimethyl sulfoxide. Factors involved in enhanced reactivity of negative ions in dipolar aprotic solvents

1984 ◽  
Vol 106 (21) ◽  
pp. 6140-6146 ◽  
Author(s):  
Tom F. Magnera ◽  
Gary Caldwell ◽  
Jan Sunner ◽  
Sigeru Ikuta ◽  
Paul Kebarle
Keyword(s):  
Dimethyl Sulfoxide ◽  
Negative Ions ◽  
Aprotic Solvents ◽  
Halide Anions ◽  
Dipolar Aprotic Solvents

Electron-transfer reactions in non-aqueous media. VII. Reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ by copper(I) in dimethyl sulfoxide-water mixtures

1983 ◽  
Vol 36 (10) ◽  
pp. 1923 ◽  
Author(s):  
JMB Harrowfield ◽  
L Spiccia ◽  
DW Watts
Keyword(s):  
Electron Transfer ◽  
Dimethyl Sulfoxide ◽  
Aqueous Media ◽  
Mixed Solvents ◽  
Transfer Reactions ◽  
Aprotic Solvents ◽  
Aqueous Mixtures ◽  
Electron Transfer Reactions ◽  
Dipolar Aprotic Solvents ◽  
Sphere Mechanism

Previous work on the reduction of a series of cobalt(III) complexes by iron(II) in dipolar aprotic solvents and in aqueous mixtures has been extended to reduction by copper(I). The greater stability of copper(I) to disproportionation in these media has permitted the study of the reduction of CoF(NH3)52+ and Co(HCOO)(NH3)52+ in range of solvents over a number of temperatures with a precision not possible in previous studies in water. The results are consistent with an inner-sphere mechanism in which the copper(I) reductant is preferentially solvated by dimethyl sulfoxide to the exclusion of water in mixed solvents.

Octahedral cobalt(III) complexes in dipolar aprotic solvents. II. Association between cis- and trans-dichlorobisethylenediamine cobalt(III) cations,[Co en2 Cl2]+, and chloride and bromide ions in the solvents NN-dimethylformamide, dimethyl sulphoxide, and LVN-dimethylacetamide

1966 ◽  
Vol 19 (1) ◽  
pp. 43 ◽  
Author(s):  
WA Millen ◽  
DW Watts
Keyword(s):  
Spectrophotometric Method ◽  
Ion Pairs ◽  
Ion Association ◽  
Ion Pair ◽  
Association Constants ◽  
Dimethyl Sulphoxide ◽  
Aprotic Solvents ◽  
Ion Association Constants ◽  
Cis And Trans ◽  
Dipolar Aprotic Solvents

Ion association constants at 30� have been determined for the cis-[Co en, Cl2]+Cl- ion pair in NN-dimethylformamide (DMF), NN-dimethylacetamide (DMA), and at 20.0�, 25.0�, and 30.0� in dimethyl sulphoxide (DMSO), by a spectrophotometric method. Association constants for the cis-[Co en2 Cl2]+Br- and the trans- [Co en2 Cl2]+Cl- ion pairs have also been determined in DMF at 30�.

Octahedral cobalt(III) complexes in dipolar aprotic solvents. XI. Anation of cis-chlorodimethylformamidebisethylenediaminecobalt(III) by bromide ion, and solvolysis and isomerization of cis-and trans-bromochlorobisethylenediaminecobalt(III) ions in anhydrous N,N-dimethylformamide

1967 ◽  
Vol 20 (12) ◽  
pp. 2623 ◽  
Author(s):  
IR Lantzke ◽  
DW Watts
Keyword(s):  
Activation Parameters ◽  
Ion Association ◽  
Aprotic Solvents ◽  
Bromide Ion ◽  
Cis And Trans ◽  
Dipolar Aprotic Solvents

The anation of the cis-chlorodimethylformamidebisethylenediaminecobalt(III) ion (cis- [CoCl(DMF) en2]2+) by bromide ion in N,N-dimethylformamide (DMF) has been studied. The reaction has an SNIIP1 mechanism, and when due allowance is made for ion association its activation parameters closely parallel those of other SNIIP anation reactions in DMF. The solvolysis and isomerization of the dichlorobisethylenediaminecobalt(III) ions (cis- and trans-[CoCl2 en2]+) and the bromochlorobisethylenediaminecobalt(III) ions (cis- and trans- CoBrCl en2]+) in DMF have been examined over a range of anion concentration. In all cases solvolysis reactions are important, although direct isomerization appears to become an important path for the reaction of the trans complexes at high anion concentrations. Solvolysis of the cis-[CoCl2 en2]+ ion involves an SN2 mechanism.1 The cis-[CoBrClen2]+, trans-[CoCl2 en2]+, and trans-[CoBrCl en2]+ ions all react by an SN1 mechanism.

Transfer activity coefficients between some dipolar aprotic solvents and alcohols of salts composed of various anions and potassium complexed with Bis(4,4'(5')-t-butylbenzo)-18-crown-6

1983 ◽  
Vol 36 (9) ◽  
pp. 1753 ◽  
Author(s):  
Jr MK Chantooni ◽  
IM Kolthoff ◽  
G Roland
Keyword(s):  
Dimethyl Sulfoxide ◽  
Stability Constants ◽  
Propylene Carbonate ◽  
Activity Coefficients ◽  
Isopropyl Alcohol ◽  
The Other ◽  
Aprotic Solvents ◽  
Transfer Activity ◽  
Dipolar Aprotic Solvents

Stability constants, Kf(LK+) and Kf(LKX) = [LKX]/[L][KX] at 25� in the dipolar aprotic solvents acetone (Me2CO), acetonitrile (MeCN), propylene carbonate (pc), N,N-dimethylformamide (HCONMe2), dimethyl sulfoxide (Me2SO), as well as in the alcohols, methanol (MeOH), isopropyl alcohol (Pr1OH), and butan -1-ol (BuOH) have been determined, L being bis(4,4'(5')-t-buty1benzo)-18- crown-6 (di(BuBo)-18-cr-6). This crown is considerably more lipophylic than is dibenzo-18-crown-6. Values of Kf(LKX) have been found from values of Kf(LK+), KA(KX) and KA(LKX). Transfer activity coefficients, Me2COγS, have been calculated (based on the Parker proposal that γ(Ph4As+) = γ(BPh4-) between acetone and the various solvents used of K+, Br-, ClO4-, P1- (picrate), LK+, KX, and LKX. It is found that K+ is more strongly solvated in Me2CO than in the other aprotic solvents of low donicity. The reverse is true between Me2CO and HCONMe2 or Me2SO (even after correcting for the Born effect).

Acceptor Numbers for Binary Mixtures of Dipolar Aprotic Solvents with Methanol

1994 ◽  
Vol 59 (6) ◽  
pp. 1349-1355 ◽  
Author(s):  
Malgorzata Podsiadla ◽  
Jadwiga Rzeszotarska ◽  
Marek K. Kalinowski
Keyword(s):  
Dimethyl Sulfoxide ◽  
Binary Mixtures ◽  
Preferential Solvation ◽  
Molar Fraction ◽  
Liquid Structure ◽  
Aprotic Solvents ◽  
Hexamethylphosphoric Triamide ◽  
Acceptor Numbers ◽  
Dipolar Aprotic Solvents

Using bis(cyano)bis(9,10-phenanthroline)iron(II) as solvatochromic indicator, the acceptor numbers, AN, were determined for binary mixtures of benzene, benzonitrile, acetonitrile, acetone, N,N-dimethylformamide, dimethyl sulfoxide and hexamethylphosphoric triamide with methanol. Deviations from linearity of the plots of AN values against the molar fraction of the components were interpreted both in terms of changes in solvent liquid structure and in cathegories of preferential solvation.

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