Radical Reductive Elimination from Tetrabenzyluranium Mediated by an Iminoquinone Ligand

Autor:	Sebastian M. Franke, Ellen M. Matson, Nickolas H. Anderson, Phillip E. Fanwick, Suzanne C. Bart, Timothy D. Cook
Rok vydání:	2014
Předmět:	Tris Ligand Organic Chemistry Alkylation Medicinal chemistry Reductive elimination Quinone Inorganic Chemistry chemistry.chemical_compound chemistry Crossover experiment Oxidation state Bibenzyl Physical and Theoretical Chemistry
Zdroj:	Organometallics. 33:1964-1971
ISSN:	1520-6041 0276-7333
Popis:	Reductive elimination from U(CH2Ph)4 (1-Ph) mediated by 4,6-di-tert-butyl-2-[(2,6-diisopropylphenyl)imino]quinone (dippiq) was observed, resulting in the formation of (dippap)2U(CH2Ph)2(THF)2 (2) (dippap = 4,6-di-tert-butyl-2-[(2,6-diisopropylphenyl)amido]phenolate) and bibenzyl. The crossover experiment with U(CD2C6D5)4 showed formation of bibenzyl-d7, indicating that reductive elimination occurs in a stepwise fashion via benzyl radical extrusion, presumably through an iminosemiquinone tris(benzyl) intermediate, (dippisq)U(CH2Ph)3. Synthesis of this intermediate was attempted by addition of the iminoquinone ligand to UI3(THF)4 to form (dippisq)UI3 (3), followed by alkylation with 3 equiv of benzylpotassium. However, this only resulted in the isolation of 2. Reduction of 3 with KC8 afforded the amidophenolate diiodide species (dippap)UI2(THF)2 (4), maintaining the tetravalent oxidation state of the uranium and reducing the ligand. Attempts at the formation of 2 via addition of 2 equiv of benzylpotassium t...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::c07eb917a4ff52b93bb0ea4da00eecb5 https://doi.org/10.1021/om4012104 Zobrazit plný text záznamu