Reflexions sobre el concepte d’aromaticitat


A dos congressos que tindran lloc el setembre proper, hi fem sengles comunicacions sobre què és i com es pot comunicar bé el concepte d’aromaticitat. Sobre l’aromaticitat molecular hi ha algunes coses interessants:

T.L. Schneider J. Chem. Educ., 2010, 87 (8), pp 793–795 Discovering Chemical Aromaticity Using Fragrant Plants

The study of aromatic compounds is an ideal time to connect the familiar with new chemical understanding, because students are already comfortable with the conventional definition of aromatic. They can extend this knowledge by learning that there is a chemical definition of aromaticity as well and a historical link between the two definitions. Because some benzene derivatives were noted to be fragrant in the early study of organic chemistry, these molecules were termed aromatic (2). This designation was given prior to 1820, before the structure of such molecules was known, and was applied to a number of odiferous carbon-rich molecules (3). We now know that benzene derivatives also have specific chemical properties in common (4). Are all scented molecules, however, chemically aromatic? This question, posed to students, led to the inquiry-based assignment detailed below.

The Many Guises of Aromaticity Is hype debasing a core chemical concept? R. Hoffmann

Aromaticity is one of the core concepts of organic chemistry. The idea began as a descriptor of the special stability of the ring of six carbons, benzene, C6H6. And importantly, of the ability of that ring to be transformed by chemically substituting the hydrogens attached to it. The reactions involved were relatively easy, the products often stable and useful. Aspirin, TNT, mescalin, vanillin, and serotonin all contain an aromatic, benzenoid core.

Aromaticity for all. S.K. Ritter, Chem. Eng. News, 2015, 93 (8), pp 37–38

Aromaticity is one of chemistry’s oldest concepts to describe the behavior of molecules. Chemists created it 150 years ago to help visualize and explain the bonding, structure, and reactivity of benzene.

What Is Aromaticity? Douglas Lloyd, J. Chem. Inf. Comput. Sci., 1996, 36 (3), pp 442–447

A brief review of the phenomenon of aromaticity is provided. The historical aspects of this property of molecules are covered, and contemporary views of aromaticity are described.