Reactions of Amines with Zwitterionic Quinoneimines: Synthesis of New Anionic and Zwitterionic Quinonoids
作者:Farba B. Tamboura、Catherine S. J. Cazin、Roberto Pattacini、Pierre Braunstein
DOI:10.1002/ejoc.200900154
日期:2009.7
which resulted from hydrolysis of the imine group and deprotonation. Under similar conditions, secondary amines led to comparable results. The cations associated with the anionic quinonoid are readily exchanged in the presence of a primary amine. Whereas for the transamination reaction basic amines react under mild conditions, slightly harsher conditions are needed for less basic amines such as piperidine
shift of the Pd(II) centers from the NPy sites to the N,O donor sites of the zwitterion core has occurred, resulting in a N2O2 tetradentate behavior of ligand L. Reaction of 4 with HCl regenerates 3 quantitatively. Chloride abstraction from 3 with AgOTf (OTf = trifluoromethanesulfonate) resulted in loss of one of the two dmba ligands and formation of an unusual tetranuclear Pd(II) complex, [Pd(dmba)}(μ-L)Pd]2(OTf)2