Core theory (chemistry)
The core theory is a view published by Auguste Laurent in 1836 on the nature of organic compounds in chemistry .
Jean Baptiste Dumas was already able to prove with candle wax that hydrogen atoms can be replaced by chlorine atoms (see history of the substitution reaction ).
This replacement of electropositive hydrogen atoms by electronegative chlorine atoms did not correspond to the conventional theory of chemical reactions according to Jöns Jakob Berzelius , since according to his theory, which is derived from electrochemistry and salts, only electropositive and electronegative particles can come together in the molecule. According to his theory, it was not possible for the electropositive hydrogen atom to be exchanged for the electronegative chlorine in a chemical reaction, as this would create a combination of electronegative chlorine and electronegative carbon. Dumas and Justus von Liebig used the term radical substitution to denote the atomic exchange of a hydrogen atom for a chlorine atom in organic chemistry.
Auguste Laurent discovered the oxidation of anthracene in anthraquinone and the substitution of hydrogen atoms by chlorine atoms in naphthalene. Laurent used the term radical for atomic nuclei. He later used the term radical for larger groups of atoms. The core core, the carbon atoms, are retained in many conversions. Minor nuclei such as hydrogen can be substituted by other nuclei such as halogens , oxygen and nitrogen . The replacement of the secondary cores takes place in accordance with the stoichiometric laws. According to this theory, electronegativity does not play an important role, only the spatial geometry of the molecule. Laurent viewed molecules as geometrical figures like pyramids. The edges (hydrogen atoms) can be replaced by other atoms (halogens or oxygen), the carbon atom forms the center.
The core theory was the later basis for the theory of the benzene ring according to Friedrich August Kekulé von Stradonitz .
The core theory was based on Leopold Gmelin 's processing of the organic part of his large handbook .
Individual evidence
- ↑ ( Google Books )
literature
- Günther Bugge: The book The Great Chemist , Volume II, Verlag Chemie, Weinheim 1974, Prof. Max Bloch: Gerhardt and Laurent , pp. 103-104, ISBN 3-527-25021-2