15016-99-6Relevant articles and documents
Polycationic states of oligoanilines based on Wurster's blue
Ito, Akihiro,Sakamaki, Daisuke,Ino, Haruhiro,Taniguchi, Aya,Hirao, Yasukazu,Tanaka, Kazuyoshi,Kanemoto, Katsuichi,Kato, Tatsuhisa
experimental part, p. 4441 - 4450 (2010/03/03)
Polycations of two oligoanilines based on Wurster's blue, N,N',N-tris[4-(dimethylamino)phenyl]-N,N',N-trimethyl1,3,5-benzenetriamine (2) and N,N'-bis(3-{N-[4-(dimethylamino)phenyl]-N-methylamino}phenyl)-N,N'-dimethyl- pphenylenediamine (3), have been generated efficiently by a stepwise oxidation procedure, Their redox behavior was characterized in terms of the embedded p-phenylenediamine (PD) units and their intramolecular connectivity, EPR analysis of the oxidized 2 and 3 species revealed the existence of high-spin species in solution. It was found that spin multiplicities of the dominant polycationic species of 2 and 3 formed by 3 equiv, of oxidant can be assigned to quartet: and doublet states, respectively on the basis of pulsed EPR spectroscopy, These results demonstrate that the intramolecular connectivity between the spin-containing units decisively influences the spin preference of the multispin systems based on oligoanilines.
Bulky alkylphosphines with neopentyl substituents as ligands in the amination of aryl bromides and chlorides
Hill, Lensey L.,Moore, Lucas R.,Huang, Rongeai,Craciun, Raluca,Vincent, Andrew J.,Dixon, David A.,Chou, Joe,Woltermann, Christopher J.,Shaughnessy, Kevin H.
, p. 5117 - 5125 (2007/10/03)
Di(tert-butyl)neopentylphosphine (DTBNpP) in combination with palladium sources provided catalysts with comparable or better activity for the Hartwig-Buchwald amination of aryl bromides than tri(tert-butyl)phosphine (TTBP) under mild conditions. DTBNpP also provided effective catalysts for amination reactions of aryl chlorides at elevated temperatures. Further replacement of tert-butyl groups with neopentyl substituents resulted in less effective ligands for amination reactions. Computationally derived cone angles showed that replacement of a tert-butyl group with a neopentyl group significantly increased the cone angle of the phosphine. The larger cone angle of DTBNpP than TTBP appears to correlate with the higher activity of catalysts derived from DTBNpP in the amination of aryl bromides. TTBP is a stronger electron donor than DTBNpP, which may explain the higher activity for TTBP-derived catalysts toward aryl chlorides.
ON THE ESR IDENTIFICATION OF PARAMAGNETIC SPECIES OBSERVED DURING SET OXIDATION OF N,N-DIMETHYL-p-ANISIDINE
Ciminale, F.,Curci, R.,Portacci, M.,Troisi, L.
, p. 2463 - 2466 (2007/10/02)
During SET oxidation of the title compound, N,N,N'-trimethyl-N'-(4-methoxyphenyl)-1,4-phenylendiamine radical cation was detected by e.s.r.; this derives from an oxidatively activated nucleophilic substitution on N,N-dimethyl-p-anisidine.Revised e.s.r. parameters for N,N-dimethyl-p-anisidinium radical are also reported.