1352171-29-9Relevant academic research and scientific papers
A polymer-supported chiral fluorinated dirhodium(II) complex for asymmetric amination of silyl enol ethers
Oohara, Tadashi,Nambu, Hisanori,Anada, Masahiro,Takeda, Koji,Hashimoto, Shunichi
, p. 2331 - 2338 (2012)
The immobilization of dirhodium(II) tetrakis[N-tetrafluorophthaloyl-(S)- tert-leucinate], [Rh2(S-TFPTTL)4], has been accomplished by copolymerization of a dirhodium(II) complex-containing monomer with styrene and 1,6-bis(4-vinylbenzyloxy)hexane as a flexible cross-linker. The polymer-supported chiral fluorinated dirhodium(II) complex catalyzed the amination of silyl enol ethers with [N-(2-nitrophenylsulfonyl)imino] phenyliodinane (NsN=IPh) to provide α-amino ketones in high yields with high levels of enantioselectivity and could be used up to 20 times as the catalyst readily withstood stirring in the presence of the solid reactant. Copyright
Structure and properties of polymer electrolyte membranes containing phosphonic acids for anhydrous fuel cells
Lee, Sung-Il,Yoon, Kyung-Hwan,Song, Myeongsoo,Peng, Huagen,Page, Kirt A.,Soles, Christopher L.,Yoon, Do Y.
, p. 115 - 122 (2012/05/20)
Recently, water-free, proton-conducting polymer electrolytes have been attracting attention because of their possible application as fuel cell membranes at intermediate temperatures (100 to 200 °C). Phosphonic acid groups are considered feasible anhydrous proton conducting moieties due to the high degree of proton self-dissociation arising from their intrinsic amphoteric character and high mobility of protonic charge carriers. In this work, we have synthesized and characterized model, phosphonic acid-functionalized proton-conducting polymers, poly(vinylbenzyloxy-alkyl-phosphonic acid)s, for the purpose of exploring the relationship between molecular design, nanostructure, and performance characteristics. These novel proton conducting materials were characterized for their thermal stability, nanostructure, and performance properties. Thermogravimetric analysis (TGA) indicates that the polymers are thermally stable up to 140 °C, where the condensation of phosphonic acid groups starts to occur. Results from small-angle X-ray scattering (SAXS) show a peak corresponding to a Bragg spacing of approximately 21-24 A, which is attributed to layerlike structure formation of the phosphonic acid containing conducting channels. The proton conductivity increases with temperature, reaching a value on the order of 3 × 10-4 S/cm at 140 °C under nominally anhydrous conditions.
