153783-13-2Relevant academic research and scientific papers
New chiral diamide ligands containing redox-active hydroquinone groups. Synthesis and results in the palladium(II)-catalyzed 1,4-diacetoxylation of 1,3-dienes
Verboom, Renzo C.,Plietker, Bernd J.,B?ckvall, Jan-E.
, p. 508 - 517 (2003)
Chiral ligands 8-11, 22 and 23 were synthesized from different chiral diamines as a new class of ligands for the Pd(II)-catalyzed 1,4-diacetoxylation of 1,3-dienes. The synthesis from the diamines and protected benzoic acids was performed in a few simple steps and gave the ligands in high overall yields. The hydroquinone groups present in the ligands are in situ oxidized to benzoquinone to give the active ligands. Application of these ligands in the 1,4-diacetoxylation reaction afforded the oxidation product with high regio- and diastereoselectivity and an enantiomeric excess up to 42% was obtained. Possible coordination modes of the metal to the ligand are discussed, and experiments were made to investigate the coordination by varying the reaction conditions or making changes to the ligands.
The E.S.R. Spectra of Some Radical Cations Derived from Aryl Ethers and Quinones
Hewgill, Frank R.,Legge, Frank,Webb, Rauleigh J.
, p. 1605 - 1612 (2007/10/02)
Radical cations were generated by oxidation of various highly substituted aryl methyl ethers with thallium(III) or lead(IV).Diprotonated radical cations of quinones with strongly electron-donating substituents were produced merely on solution in trifluoro
