Electromerism
Electromerism is a type of isomerism between a pair of molecules (electromers, electro-isomers) differing in the way electrons are distributed among the atoms and the connecting chemical bonds.[1] In some literature electromerism is equated to valence tautomerism,[2] a term usually reserved for tautomerism involving reconnecting chemical bonds.[3]
One group of electromers are excited electronic states, but isomerism is usually limited to ground state molecules. Another group of electromers are also called redox isomers: metal ions that can exchange their oxidation state with their ligands (see non-innocent ligand). One of the first instances involved a cobalt(II)-quinone complex vs the related cobalt(III)-semiquinone species. Some metalloporphyrins exist as electromers.[4][5] as well as a set without a metal.[6]
References
[edit]- ^ Bally, T. (2010). "Isomerism: The same but different" (PDF). Nature Chemistry. 2 (3): 165–166. Bibcode:2010NatCh...2..165B. doi:10.1038/nchem.564. PMID 21124473.
- ^ Evangelio, E.; Ruiz-Molina, D. (2005). "Valence Tautomerism: New Challenges for Electroactive Ligands". European Journal of Inorganic Chemistry. 2005 (15): 2957. doi:10.1002/ejic.200500323.
- ^ Jones, L. W. (1917). "Electromerism, A Case of Chemical Isomerism Resulting from a Difference in Distribution of Valence Electrons". Science. 46 (1195): 493–502. Bibcode:1917Sci....46..493J. doi:10.1126/science.46.1195.493. PMID 17818241.
- ^ Puschmann, F.; Harmer, J.; Stein, D.; Rüegger, H.; De Bruin, B.; Grützmacher, H. (2010). "Electromeric rhodium radical complexes". Angewandte Chemie International Edition in English. 49 (2): 385–389. doi:10.1002/anie.200903201. PMID 19957252.
- ^ Puschmann, F.F.; Grützmacher, H.; de Bruin, B. (2010). "Rhodium(0) Metalloradicals in Binuclear C−H Activation". Journal of the American Chemical Society. 132 (1): 73–75. doi:10.1021/ja909022p. PMID 20000835.
- ^ Müller, B.; Bally, T.; Gerson, F.; De Meijere, A.; Von Seebach, M. (2003). ""Electromers" of the tetramethyleneethane radical cation and their nonexistence in the octamethyl derivative: interplay of experiment and theory". Journal of the American Chemical Society. 125 (45): 13776–13783. doi:10.1021/ja037252v. PMID 14599217.