The first palladium(iv) aryldiazenido complex: relevance for C-C coupling
Marzieh Daryanavard1, David Armstrong1, Alan J Lough2
1University of Toronto, Mississauga Campus, 3359 Mississauga Road, Mississauga, Ontario, Canada L5L 1C6. ulrich.fekl@utoronto.ca.
Abstract:
Overall two-electron oxidative addition of the aryldiazonium cation para-methoxybenzenediazonium (pmbd+) to [(Tp*)PdIIMe2]- (Tp*- = hydridotris-(3,5-dimethylpyrazolyl)borate) produces the first characterized palladium(iv) aryldiazenido complex, [(Tp*)PdIVMe2(pmbd)] (pmbd- = para-methoxybenzenediazenido). Thermolysis in benzene forms a mixture of products that contains [(Tp*)PdIVMe3] and the C-C coupled product, 4,4'-dimethoxybiphenyl. The use of acetone as the thermolysis solvent changes the product distribution towards the formation of anisole. While some involvement of two-electron pathways in the decomposition cannot be ruled out, radicals, through one-electron steps, are involved in the major pathways for decomposition. The involvement of radicals is confirmed by the solvent dependent nature of the product distribution and by observing that the added N-tert-butyl-α-phenylnitrone efficiently traps aryl radicals.
More Related Videos
11:44Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-phosphinetriyltripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
07:20Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Related Concept Videos
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Diazonium Group Substitution: –OH and –H
¹H NMR: Long-Range Coupling
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
