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The crystal structure of -sodium benzenediazotate-4-sulphonate shows this to be the - and not the -isomer 相似文献
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[structure: see text] A series of ruthenium(II) complexes containing BINOL-based monodonor phosphorus ligands have been prepared and applied to the asymmetric catalysis of the hydrogenation of aryl/alkyl ketones. The best ligands for this application are those which contain an aromatic groups with either a methoxide or bromide on the ortho position. Using these ligands, alcohols with ee's of up to 99% are formed. 相似文献
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Nathaniel W. Alcock Adam J. Clarke William Errington Ana Maria Josceanu Peter Moore Simon C. Rawle 《Supramolecular chemistry》2013,25(3-4):281-291
Abstract A series of azamacrocycles which have been N-functionalised with pendent pyridylmethyl-(pyCH2-), bipyridylmethyl-(bipyCH2-) and terpyridylmethyl- (terpyCH2-) arms have been synthesised and characterised, and some of their coordination chemistry with transition metal ions is reported. By attaching the pendent-arms at the 5- rather than the 6-position of the py, bipy and terpy, new ligands are generated which can be used to form polynuclear metal complexes in a controlled and systematic fashion. Fluorescent pH and transition metal ion sensors have been developed by reacting the azamacrocyclic N-pendent bipyCH2 arm(s) with cis-[Ru(bipy)2Cl2], to give macrocycles with up to four attached [Ru(bipy)3]2+ groups. That based on 1,4,7-triazacyclononane (9N3), with three attached [Ru(bipy)3]2+ groups, has a first photo excited state pKa of 7.1, and is a useful fluorescent sensor for physiological pH at below micromolar concentrations. The analogous derivative of cyclam (1,4,8,11-tetraazacyclotetradecane) carrying four [Ru(bipy)3]2+ groups has a first photo excited state pKa of 5.7, allowing kinetic and thermodynamic fluorescence studies of metal ion uptake by an azamacrocycle at neutral pH without complications from protonated species. A pre-organised hexadentate tris(2,2′-bipyridyl) chelating ligand, 1,4,7-tris(2′,2″-bipyridyl-5′-ylmethyl)-1,4,7-triazacyclononane (L) has been developed, and crystal structures of mononuclear complexes [M(LH)]3+ (M = Ru, Cu) are reported. In [M(LH)]3+ the azamacrocyclic N-atoms are non-coordinating to M, but have a very high affinity for a single proton trapped in the macrocyclic cavity. An analogous and potentially nonadentate ligand has been developed based on 9N3 with three N-pendent terpyCH2-arms. 相似文献
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F. H. Alcock 《Analytical and bioanalytical chemistry》1907,46(10-11):738-738
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Inter-oxide compounds of rare earth and transition metal oxides can be made highly nonstoichiometric by the partial substitution of divalent ions, such as strontium, for the rare earth element. These compounds become highly conductive when suitably treated in oxygen at high temperatures, and have been found to function as efficient oxidation catalysts at low temperatures between 100–300°C. The thermodynamics, transport properties and catalytic behavior for CO and CH4 oxidation of some systems having the perovskite or the K2NiF4 structure are discussed, e.g. La1−xSrxMO3−δ(M=Cr,Mn,Fe,Co,Y) and La2−xSrxCuO4−δ. The catalytic behavior is similar for the Cr,Mn,Fe and Co perovskites, but the solid electrolyte La0.8Sr0.2YO2.9 has no effect in CO oxidation but the greatest activity for CH4 oxidation. 相似文献