Über Komplexisomerie

Abstract

l ) Habilitationsschrift, Bonn 1925. *) Diss. Bonn 1926. Herr Mischnat hat insbesondere die Vcrbindungen der Nitrokgrper mit l-Brom-4-naphtylamin, l-Chlor-4-naphtylamin, l-Chlor-2-naphtylamin, 1,6-Dibrom-2-naphtylamin u. a. untereucht, die Starke dee baaischen Charakters der halogenierten Naphtylamine nach B r e d i g gemessen nnd die Diagramme nach R h e i n b o l d t aufgenommcn. 3, Z. n. Ch. 137, 275 (1924).l i e r t e l ,

Aromatic Molecular Complexes of the Electron Donor-Acceptor Type.

“…For example, the red to brown color of solutions of iodine in aromatic solvents, as contrasted to the violet color of the halogen in inert solvents such as carbon tetrachloride, was ascribed to the formation of iodine solvates (174) before convincing proof of the interaction was provided. The intense color (orange to red) of the solid 1:1 complexes formed by certain weakly basic aromatic amines and picric acid served to distinguish these addition products structurally from the yellow salt-like amine picrate formed by the more strongly basic amines (131,135). The relative stabilities of complexes of a series of aromatic substances with a particular acceptor-type reagent have been assigned on the basis of the differences in color of the addition products.…”

Development of Conductive Organic Molecular Assemblies: Organic Metals, Superconductors, and Exotic Functional Materials

“…If more than one type of force field was present in each of the components then isomeric molecular complexes could be obtained depending on which pair of force fields predominated-termed as complex isomerization by Hertel. 648,649 For example, aniline and its derivatives are bi-functional molecules concerning the charge(electron)-transfer and PT interactions ( Fig. 80): anilines have an electron-donating ability as well as proton-accepting ability (Brønsted base).…”

“…For PT interaction, pK a , pK b , and Coulomb energy are the important parameters, while I D , E A , and M should be taken into account for CT interaction. As early as the 1920s and 1930s, Hertel et al [648][649][650] noticed that ''Progressive weakening of the acid-base interaction and strengthening of the donor-acceptor interaction should produce binary compounds which range in type from ''true phenolates'' at one end of the series to ''true molecular compounds'' at the other. In the intermediate situations, same partners form either phenolates or molecular compounds, depending on ambient conditions''-according to a paper by Herbstein.…”

Organic Charge-Transfer Complexes

“…1OT The presence of paramagnetism has been shown in this way in the complexes of iV2VN'iV'-tetramethyl-/>-phenylenediamine with p -benzoquinone and its tetrahalogeno-derivatives and also with tetrabromo-o -benzoquinone 119 » 168 . Paramagnetism had been detected previously 169 in the complex of NN-dimethylaniline with chloranil. According to Bijl et al 113 , the complex of NNN'N'-tetvamethyl-/>-phenylenediamine with chloranil contains 0.4% of the diradical form, while that with tetrabromo-o-benzoquinone, which has a considerably higher redox potential, contained 80%.…”