Magnitudes of the inductive effects of the nitro and nitrate groups

1966 ◽  
Vol 15 (8) ◽  
pp. 1435-1437
Author(s):  
V. I. Slovetskii ◽  
A. A. Fainzil'berg
Keyword(s):  
Inductive Effects

ChemInform Abstract: STRUCTURE OF FLUOROMETHYL RADICALS. CONJUGATIVE AND INDUCTIVE EFFECTS

1978 ◽  
Vol 9 (25) ◽  
Author(s):  
F. BERNARDI ◽  
W. CHERRY ◽  
S. SHAIK ◽  
N. D. EPIOTIS
Keyword(s):  
Inductive Effects ◽  
Abstract Structure

The addition of 2,4-dinitrobenzenesulphenyl chloride to 1,3-disubstituted allenes: a reexamination

1979 ◽  
Vol 57 (1) ◽  
pp. 119-127 ◽  
Author(s):  
Dennis G. Garratt ◽  
Pierre Beaulieu
Keyword(s):  
Double Bond ◽  
Chloride Solution ◽  
Methylene Chloride ◽  
Effective Mechanism ◽  
Substituent Group ◽  
Methylene Chloride Solution ◽  
Inductive Effects ◽  
Allene System

The reaction of 2,4-dinitrobenzenesulphenyl chloride with eight alkyl 1,3-disubstituted allenes in methylene chloride solution has been investigated. In contrast to earlier reports, attack by sulphur is found to occur exclusively at the central allenic carbon. The direction of approach of sulphenyl chloride leads preferentially to the formation of the E isomers in accord with the concept of steric approach control. The ratio of E to Z alkene is found to increase as the bulk of the substituent group cis to the arylthio group increases. We observe, however, very little regioselectivity with respect to which of the mutually perpendicular π bonds of the allene system is attacked, suggesting the presence of an effective mechanism for transmission of inductive effects to the more distant double bond.

scholarly journals Etude par résonance magnétique nucléaire de composés organiques contenant des chalcogènes. II. L'éther de diphényle et ses analogues soufré, sélénié et telluré

1979 ◽  
Vol 57 (22) ◽  
pp. 2967-2970 ◽  
Author(s):  
Gabriel Llabrès ◽  
Marcel Baiwir ◽  
Léon Christiaens ◽  
Jean-Louis Piette
Keyword(s):  
Crystal Structure ◽  
Theoretical Calculations ◽  
Heavy Atom ◽  
Mesomeric Effect ◽  
Heavy Atom Effect ◽  
Inductive Effects ◽  
Structure Determinations ◽  
Résonance Magnétique ◽  
Atom Effect ◽  
Good Agreement

The 1Hmr study of the title compounds has revealed a screw conformation, with defined interconversion processes, in good agreement with crystal structure determinations and theoretical calculations. The mesomeric effect of the heteroatom is smaller than in the anisole series, due to steric inhibitions.The 13Cmr enhances, to some extent, these conclusions. In the case of Te compounds, a heavy atom effect adds to the classical mesomeric and inductive effects to account for the experimental observations.

scholarly journals 5-ACETYL-8-HYDROXYQUINOLINE AND 5-FORMYL-8- HYDROXYQUINOLINE: CHELATING AGENTS FOR COMPLEXOMETRIC TITRATIONS

2019 ◽  
Vol 16 (31) ◽  
pp. 765-777
Author(s):  
Roberto FERNANDEZ-MAESTRE ◽  
Alonso J MARRUGO-GONZÁLEZ
Keyword(s):  
Environmental Remediation ◽  
Chelating Agents ◽  
Organic Ligand ◽  
Formation Constants ◽  
Oxidation Reduction ◽  
Inductive Effects ◽  
Technological Developments ◽  
Metal Organic ◽  
Large Formation ◽  
Derivatives Of

Metal–organic ligand complexes are essential to many technological developments from protein supramolecular assemblies to solvent extraction, complexometric titrations, and environmental remediation. We studied the chelating and acid-base properties in ethanol of two derivatives of 8-hydroxyquinoline (Q), 5-acetyl-8-hydroxyquinoline (A) and 5-formyl-8-hydroxyquinoline (F), of which applications as chelators are unknown. The ligands acidity followed the order F (pKa1 2.9; pKa2 9.5)> A (pKa1 4.8; pKa2 9.6)> Q (pKa1 5.3; pKa2 10.0) due to inductive effects of electronegative groups, formyl in F and acetyl in A. The higher acidity of F with respect to A was due to the higher electronegativity of the formyl group in F. This acidity order was reflected in larger formation constants of F-metal complexes with pKf values of 32 (Fe3+), 27.1 (Cu2+), 26.2 (Cu2+), and 24.9 (Pb2+), than with A, with pKf values of 31, 22.5, 21.4 and 21.2 with these metals, or the pKf values in the literature for Q. In summary, A and F resulted excellent chelators for metals in complexometric titrations with large formation constants; these large formation constants recommend the application of these compounds in masking, preconcentration, and titration of metals by complexation and oxidation-reduction reactions.

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