An In‐Depth Look at the Reactivity of Non‐Redox‐Metal Alkylperoxides

• Published in: Angewandte Chemie Vol. 131; no. 25; pp. 8614 - 8618
• Main Authors: Pietrzak, Tomasz, Justyniak, Iwona, Kubisiak, Marcin, Bojarski, Emil, Lewiński, Janusz
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 17-06-2019
• Subjects: Alkyl compounds; Alkylgruppen; Base metal; Chemistry; Coordination compounds; Disauerstoff; Ligands; Metal hydroxides; Metals; Organometallic compounds; Oxidation; Oxygen transfer; Oxygenation; Oxygenierungen; Peroxide; Zinc; Zink
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.201904380

Over the past 150 years, a certain mythology has arisen around the mechanistic pathways of the oxygenation of organometallics with non‐redox‐active metal centers as well as the character of products formed. Notably, there is a widespread perception that the formation of commonly encountered metal alkoxide species results from the auto‐oxidation reaction, in which a parent metal alkyl compound is oxidized by the metal alkylperoxide via oxygen transfer reaction. Now, harnessing a well‐defined zinc ethylperoxide incorporating a β‐diketiminate ligand, the investigated alkylperoxide compounds do not react with the parent metal alkyl complex as well as Et2Zn to form a zinc alkoxide. Upon treatment of the zinc ethylperoxide with Et2Zn, a previously unobserved ligand exchange process is favored. Isolation of a zinc hydroxide carboxylate as a product of decomposition of the parent zinc ethylperoxide demonstrates the susceptibility of the latter to O−O bond homolysis.
Trotz der oxidierenden Eigenschaften von Zinkalkylperoxiden reagieren diese weder mit dem Alkylzink‐Ausgangskomplex noch mit der homoleptischen Ethylzink‐Verbindung unter Bildung von Zinkalkoxiden. Zudem zeigt die Isolierung eines Zinkhydroxidacetats als Produkt der Umwandlung des Ausgangs‐Zinkethylperoxids eine starke Neigung des Letztgenannten zur O‐O‐Bindungshomolyse.