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991.
Jordan BJ Pollier MA Ofir Y Joubanian S Mehtala JG Sinkel C Caldwell ST Kennedy A Rabani G Cooke G Rotello VM 《Chemical communications (Cambridge, England)》2008,(14):1653-1655
We report the modulation of the absorbance of a flavin push-pull derivative through specific recognition by a complementary diamidopyridine (DAP), shifting the flavin intramolecular charge transfer band by approximately 30 nm. 相似文献
992.
Rio-Echevarria IM White FJ Brechin EK Tasker PA Harris SG 《Chemical communications (Cambridge, England)》2008,(38):4570-4572
Benzohydroxamic acid is shown to be an unexpectedly good ligand for iron(iii) oxides, favouring surface attachment to the formation of trisbenzohydroxamato complexes, which are known to have very high thermodynamic stability in solution. 相似文献
993.
Lithium, used in conjunction with sodium metal, produces a high yield of carbazole when reacted with phenothiazine-5-oxide or phenothiazine-5,5-dioxide. A high yield of 9-ethylcarbazole is also produced when these reagents react with 10-ethylphenothiazine, 10-ethylphenothiazine-5-oxide, and 10-ethylphenothiazine-5,5-dioxide. Degassed Raney nickel produces carbazole in high yield when reacted with phenothiazine and phenothiazine-5-oxide. A moderate yield of 9-ethylcarbazole is produced when n-butyllithium is reacted with 10-ethylphenothiazine-5-oxide. 相似文献
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999.
Alexey A. Popov Dr. Natalia B. Shustova Olga V. Boltalina Dr. Steven H. Strauss Prof. Lothar Dunsch Prof. Dr. 《Chemphyschem》2008,9(3):431-438
A spectroelectrochemical study of the two isostructural asymmetric perfluoroalkyl derivatives C1‐7,24‐C70(CF3)2 and C1‐7,24‐C70(C2F5)2 is presented. Reversible formation of their stable monoanion radicals is monitored by cyclic voltammetry and by in situ ESR‐Vis‐NIR spectroelectrochemistry. The ESR spectrum of the C70(CF3)2?. radical is a 1:3:3:1 quartet with a 19F hyperfine coupling constant (a(F)) of 0.323(4) G, demonstrating that the unpaired spin is coupled to only one of the two CF3 groups. The 13C satellites are assigned to specific carbon atoms. The ESR spectrum of the C70(C2F5)2?. radical is an apparent octet with an apparent a(F) value of 0.83(2) G. DFT calculations suggest that this pattern is due to the superposition of spectra for four nearly isoenergetic C70(C2F5)2?. conformers. Time‐dependent DFT calculations suggest that the NIR band at 1090 nm exhibited by both C70(Rf)2?. radical anions is assigned to the SOMO→LUMO+3 transition. The analogous NIR band exhibited by the closed‐shell C70(CF3)22? dianion was blue‐shifted to 1000 nm. 相似文献
1000.
Steven Baldelli Prof. 《Chemphyschem》2008,9(16):2291-2298
In situ techniques are indispensable to understanding many topics in surface chemistry. As a consequence, several spectroscopic methods have been developed to provide molecular‐level information that only spectroscopy can supply. However, as important as this information is, it is just as critical to realize that nearly all surfaces under investigation have spatial heterogeneities of the order of nanometers to millimeters; thus, spatial analysis is very important to the overall interpretation. This Minireview focuses on a few of the recent developments in spectroscopic techniques that can provide spatial, spectroscopic, and in situ information. These techniques include photo‐electron microscopy, infrared and Raman imaging, and nonlinear optical imaging vibrational spectroscopy as applied to topics in corrosion, catalysis and self‐assembled monolayers. 相似文献