Fluorinated alkoxides. 16. Structure of a dinuclear imino alkoxy complex of copper(II)

1981 ◽  
Vol 20 (1) ◽  
pp. 272-275 ◽  
Author(s):  
Donna L. Barber ◽  
Stephen J. Loeb ◽  
John W. L. Martin ◽  
Nicholas C. Payne ◽  
Christopher J. Willis
Keyword(s):  
Fluorinated Alkoxides

FULLY FLUORINATED ALKOXIDES: PART I. TRIFLUOROMETHOXIDES OF ALKALI METALS

1965 ◽  
Vol 43 (7) ◽  
pp. 1893-1898 ◽  
Author(s):  
M. E. Redwood ◽  
C. J. Willis
Keyword(s):  
Relative Stability ◽  
Alkali Metals ◽  
Reversible Reaction ◽  
Metal Fluoride ◽  
Factors Affecting ◽  
Ionic Solids ◽  
Fluorinated Alkoxides ◽  
Carbonyl Fluoride

The preparation is described of the trifluoromethoxides of the heavier alkali metals, i.e. MOCF3 where M = K, Rb, or Cs. These are stable, crystalline, ionic solids made by the reversible reaction of carbonyl fluoride with the appropriate metal fluoride. No trifluoromethoxides could be prepared from lithium, sodium, barium, or thallium(I) fluorides. Factors affecting the relative stability of such compounds are discussed.

Volatile fluorinated alkoxides of the alkali metals

1970 ◽  
Vol 9 (11) ◽  
pp. 2590-2591 ◽  
Author(s):  
Robert E. A. Dear ◽  
William B. Fox ◽  
R. J. Fredericks ◽  
Everett E. Gilbert ◽  
Dale K. Huggins
Keyword(s):  
Alkali Metals ◽  
Fluorinated Alkoxides

Fluorinated alkoxides. Part XI. Studies on highly fluorinated amino-alcohols and their metal derivatives

1977 ◽  
Vol 55 (13) ◽  
pp. 2465-2472 ◽  
Author(s):  
In-Soon Chang ◽  
Christopher J. Willis
Keyword(s):  
Donor Site ◽  
Amino Alcohols ◽  
Formation Constants ◽  
Intramolecular Proton Transfer ◽  
Nitrogen Donor ◽  
Metal Derivatives ◽  
Fluorinated Alcohol ◽  
Fluorinated Alkoxides ◽  
Trifluoromethyl Groups ◽  
Steric Influence

We describe the synthesis of a number of difunctional molecules in which the fluorinated tertiary alcohol grouping, -C(CF3)20H, is combined with a nitrogen donor site such as an amino-group or a pyridine ring. In all cases, zwitterionic behaviour in solution is found resulting from intramolecular proton transfer from the acidic fluorinated alcohol to the nitrogen, and this sometimes persists in the solid state, e.g. NH2CH2CH2C(CF3)20H exists as the dipolar ion +NH3CH2CH2C(CF3),0-. Measurements of pK values suggest that the behaviour of the fluorinated amino-alcohols may be compared with that of the amino-acids, subject to changes to be expected from the lower acidity of the -C(CF3)20H group. Metal complexes of the fluorinated amino-alcohols form readily; specifically, neutral complexes of Co2+, Ni2+, and Cu2+ of formula M(L),, where L is an ionized amino-alcohol chelating through the ionized hydroxy group and the nitrogen atom. Measurements of formation constants show that the six-membered chelate rings are the most stable, while a comparison of the stabilities of fluorinated amino-alkoxy complexes with those of analogous aminoacids shows that the former are less stable: this is attributed to the steric influence of the trifluoromethyl groups.

Fluorinated alkoxides. Part XII. Studies on potentially tridentate fluorinated diols; zwitterionic and five-coordinate complexes of Ni2+ and Cu2+

1978 ◽  
Vol 56 (17) ◽  
pp. 2369-2373 ◽  
Author(s):  
Stephen J. Loeb ◽  
John W. L. Martin ◽  
Christopher J. Willis
Keyword(s):  
Steric Effects ◽  
Bidentate Ligands ◽  
Tridentate Ligands ◽  
The Third ◽  
Complexing Ability ◽  
Fluorinated Alcohol ◽  
Fluorinated Alkoxides

The complexing ability towards Ni2+ and Cu2+ of the potentially tridentate ligands HOC(CF3)2CH2C(O)CH2C(CF3)2OH, HOC(CF3)2CH2CH(OH)CH2C(CF3)2OH, and HOC(CF3)2CH2CH2N:C(CH3)CH2C(CF3)2OH has been studied. The first two act as bidentate ligands, uninegative or dinegative according to the extent of ionization of the fluorinated alcohol groups; when both were ionized, the complexes had a zwitterionic structure. The third ligand was exclusively tridentate in its complexes; this difference is ascribed to its greater flexibility. Both four- and five-coordinate complexes of nickel were observed, the latter being produced either by choice of co-ligands or by solvation, but no six-coordinate complex was formed in this series. Limitations on coordination for the metal are ascribed to steric effects.

Fluorinated Alkoxides. Part VIII. Mixed Ligand Complexes of Perfluoropinacol with Ni2+, Pd2+, Pt2+ and Cu2+. Solvation Equilibria between 4- and 5-coordinate Ni2+

1975 ◽  
Vol 53 (6) ◽  
pp. 809-816 ◽  
Author(s):  
W. Stafford Cripps ◽  
Christopher J. Willis
Keyword(s):  
Metal Ion ◽  
Nickel Complexes ◽  
Mixed Ligand ◽  
Ligand Field ◽  
Electronic Effects ◽  
Unusual Behavior ◽  
Planar Structures ◽  
Square Planar ◽  
Phosphorus Containing ◽  
Fluorinated Alkoxides

Perfluoropinacol, (CF3)2C(OH)C(OH)(CF3)2, ionizes by loss of two protons, and the resulting dinegative ion (PFP2−) chelates to Ni2+, Pd2+, Pt2+, and Cu2+. A variety of stable neutral complexes may be isolated if the tetracoordination of the metal ion is completed with two monodentate or one bidentate nitrogen- or phosphorus-containing ligands; square-planar structures are invariably found. The structures of these complexes are contrasted with those of analogous halides, and it is concluded that electronic effects are predominant in determining them, although steric influences may sometimes be important. The ligand field strength of the perfluoropinacolato ion is approximately equal to that of the thiocyanate ion.The nickel complexes Ni(PFP)22− and (PFP)Ni(RNHCH2CH2NHR) react with donor solvents (water, methanol, pyridine, etc.) to give equilibria between four- and five-coordinate solvated species; six-coordinate species are not observed. This unusual behavior is attributed to the steric hindrance imposed by the bulk of the PFP2− ligand.

Fluorinated alkoxides. Part X. Template syntheses leading to fluorinated β-imino-alkoxy complexes of four- and five-coordinate nickel(I1) and copper(I1)

1977 ◽  
Vol 55 (13) ◽  
pp. 2459-2464 ◽  
Author(s):  
John W. L. Martin ◽  
Christopher J. Willis
Keyword(s):  
Metal Ions ◽  
Metal Ion ◽  
Condensation Reactions ◽  
Template Condensation ◽  
Square Planar ◽  
Fluorinated Alkoxides

Hexafluorodiacetonealcohol, HFDA, HOC(CF3)2CH2COCH3, is sufficiently acidic to coordinate to metal ions in an ionized form as a chelating, uninegative ligand. Complexes of Ni2 + and Cu2+ may be isolated, most conveniently by using a tridentate nitrogen-containing macrocycle as co-ligand so that five-coordinate unipositive compounds are produced. In the presence of metal ions, HFDA readily undergoes template condensation reactions with diamino-ethane or -propane to give conplexes of ionized β-imino alcohols, e.g. -OC(CF3)2- CH2C(CH3) : N(CH2)2N : C(CH3)CH2C(CF3)20- ; these conplexes are neutral and square planar but become five-coordinate by solvation in, e.g., pyridine. The use of triamines H2N- (CH2),NH(CH2).NH2 (where n = 2 or 3) in template syntheses with HFDA gives complexes in which the metal ion is five-coordinate; these do not undergo solvation.

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