Oxygen as moderator in the zinc-mediated reduction of aromatic nitro to azoxy compounds
作者:Faiz Ahmed Khan、Ch. Sudheer
DOI:10.1016/j.tetlet.2009.02.122
日期:2009.7
A simple and useful protocol for the reduction of nitro arenes to their corresponding azoxy derivatives by employing zinc and NH4Cl in a mixture of [bmim][BF4] and water is described. The selectivereduction of nitro to azoxy is attributed to the hitherto unknown moderating effect of oxygen on zinc metal.
Fluorescent ion indicators for cadmium and lanthanide ion detection
申请人:Gee Kyle
公开号:US08604243B2
公开(公告)日:2013-12-10
The present invention provides a metal chelator and methods that facilitate binding, detecting, monitoring and quantitating of heavy metal ions in a sample. This metal chelating moiety has the following formula
Disclosed is a cyclic carbodiimide compound useful as an end-capping agent for polymer compounds. The cyclic carbodiimide compound is represented by the following formula (i):
wherein X is a specific divalent group or tetravalent group, q is 0 when X is a divalent group, while q is 1 when X is a tetravalent group, and Ar
1
to Ar
4
are selected from aromatic groups each independently optionally substituted with a group that serves as X.
Synthesis and spectroscopic properties of new bis-tetrazoles
作者:Agnieszka Pazik、Anna Skwierawska
DOI:10.1007/s10847-012-0219-4
日期:2013.12
Syntheses of N,N′-phenyltetrazole podands link with aliphatic chains containing oxygen, nitrogen and sulphur atoms, are described. The complexing properties of these compounds towards metal cations (Fe2+, Cu2+, Zn2+, Co2+, Ni2+) were investigated by absorption and infrared spectroscopy. The UV–Vis titrations were performed to estimate the stability constant values of the respective complexes with Cu2+ ion. Changes in UV–Vis absorption spectra and IR spectra of compound 6 under various concentrations of Cu2+ ion in methanol suggest formation of very unstable complex. The structure of ligand 2 has been deduced by X-ray crystallography.
Stereochemistry of crown ethers. I. Conformational and dynamic behaviour ofN-tosyl-substituted diaza crown ethers
作者:E. Kleinpeter、M. Gäbler、W. Schroth
DOI:10.1002/mrc.1260260507
日期:1988.5
The variable-temperature 1H and 13C NMR spectra of some N-tosyl diaza crown ethers have been obtained. They are discussed with respect to the preferred conformers of the crowns and the free energies of activation of the interconversional process of the large ring. Both the preferred conformers and the ring interconversional barriers have been found to be strongly dependent on the structure and the ring size of the studied compounds.