Colorimetric sensing of Cu(ii) by 2-methyl-3-[(pyridin-2-ylmethyl)-amino]-1,4-naphthoquinone: Cu(ii) induced deprotonation of NH responsible for color changes.

Content Provider	Semantic Scholar
Author	Wu, Shu-Pao Huang, Ray-Yui Du, Kun-Ju
Copyright Year	2009
Abstract	1,4-Naphthoquinone based chemosensors and detect only the presence of Cu(2+) ions among other transition metal ions by changing color from orange to dark blue. Chemosensors and function as tridentate ligands, which bind Cu(2+) ions through three functional groups: an amine nitrogen, a pyridine nitrogen and a quinone oxygen. On addition of Cu(2+), both and exhibit a 168 nm red shift in absorption wavelength (pH 7.0). The effect on pH by the formation of these Cu(2+) complexes was determined by UV-vis spectroscopic pH titration. In the pH range of 6-7.5, a maximum was observed at 634 nm and exhibited the formation of deprotonated -Cu(2+) and -Cu(2+) complexes. A reversible color change (orange-blue-orange) was observed when chemosensor was mixed with Cu(2+) in CH(3)CN. This represents a reversible process of deprotonation and re-protonation of the -Cu(2+) complexes and also demonstrates the short half-life of thr deprotonated -Cu(2+) complexes in CH(3)CN.
Starting Page	1
Ending Page	2
Page Count	2
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://ir.nctu.edu.tw/bitstream/11536/7933/1/000266866400016.pdf
PubMed reference number	19513483v1
Alternate Webpage(s)	https://doi.org/10.1039/b822613j
DOI	10.1039/b822613j
Journal	Dalton transactions
Volume Number	24
Language	English
Access Restriction	Open
Subject Keyword	1,4-benzoquinone 1,4-naphthoquinone Amines Blood urea nitrogen measurement Ions Ligands Neonatal hemochromatosis Oxygen Pyridines Threonine Titration Method Transition Elements wavelength
Content Type	Text
Resource Type	Article