Optical Devices Constructed from Multiresponsive Microgels
作者:Qiang Matthew Zhang、Wenwen Xu、Michael J. Serpe
DOI:10.1002/anie.201402641
日期:2014.5.5
Novel multiresponsivemicrogels based on poly(N‐isopropylacrylamide) were synthesized to contain triphenylmethane leucohydroxide, and used to construct etalons. The optical properties of the resultant etalons were investigated, and their response to ultraviolet and visible irradiation, solution pH changes, and the presence of a mimic of the nerve agent Tabun characterized. We clearly show that the
Iron Complexes Bearing Diphosphine Ligands with Positioned Pendant Amines as Electrocatalysts for the Oxidation of H<sub>2</sub>
作者:Tianbiao Liu、Qian Liao、Molly O’Hagan、Elliott B. Hulley、Daniel L. DuBois、R. Morris Bullock
DOI:10.1021/om501289f
日期:2015.6.22
The synthesis and spectroscopic characterization of (CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)Cl, [3-Cl] (where C5F4N is a tetrafluoropyridyl substituent and (P2N2Bn)-N-tBu = 1,5-dibenzyl-3,7-di(tert-butyl)-1,5-diaza-3,7-diphosphacyclooctane), are reported. Complex 3-Cl and [(CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)Cl], 4-Cl, are precursors to intermediates in the catalytic oxidation of H2, including (CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)H (3-H), (CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)H (4-H), [(CpNFe)-N-C5F4((P2N2Bn)-N-tBu)]BAr4F ([3](BAr4F), [(CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)]BAr4F ([4](BArF4), [(CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)(H2)]BAr4F ([3-H2]BAr4F), and [(CpFe)-Fe-C5F4N((P2N2Bn)-N-tBu)H]BAr4F ([4-FeH(NH)]BAr4F). All of these complexes were characterized by spectroscopic and electrochemical studies; 3-Cl, 3-H, and 4-Cl were also characterized by single crystal diffraction studies. 3-H and 4-H are electrocatalysts for H2 (1.0 atm) oxidation in the presence of an excess of the amine bases N-methylpyrrolidine, Et3N or iPr2EtN. Turnover frequencies at 22 degrees C for 3-H and 4-H with N-methylpyrrolidine as the base are 2.5 and 0.5 s1, and overpotentials at Ecat/2 are 235 and 95 mV, respectively. Studies of individual chemical and electrochemical reactions of the various intermediates provide important insights into the factors governing the overall catalytic activity for H2 oxidation.