Metall-π-Komplexe von Benzolderivaten, XX [1]. Über die Cokondensation des Phenanthrens mit Chromatomen - Reaktivität, Redoxverhalten, ESR-und NMR-spektroskopische Untersuchungen / Metal-π-Complexes of Benzene Derivatives, XX [1]. Cocondensation of Phenanthrene with Chromium Atoms - Reactivity, Redox Behavior, ESR and NMR Spectroscopic Investigation

Abstract

<jats:p>Cocondensation of chromium atoms with phenanthrene vapor affords bisη<jats:sup>1,2,3,4,10a,4a</jats:sup>- phenanthrene)chromium (4). <jats:sup>1</jats:sup> NMR spectroscopy reveals, that the diastereomers 4 (rac) and 4' (meso) are formed in a 2:1 ratio. Cyclic voltammetric studies on 4 show, that four oxidation states are accessible:<jats:inline-formula><jats:alternatives><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/Untitled-1.jpg" /></jats:alternatives></jats:inline-formula>[E° ═ -2.235 (rev.), -0.651 (rev.), + 0.82 (irrev.) V vs. SCE]. The radical ions <jats:inline-formula><jats:alternatives><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/Untitled-2.jpg" /></jats:alternatives></jats:inline-formula> are characterized by ESR spectro­scopy in fluid and rigid solutions. Prominent feature of these species is the inverse relative magnitude of the g-tensor components: <jats:inline-formula><jats:alternatives><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/Untitled-3.jpg" /></jats:alternatives></jats:inline-formula>.</jats:p>