263382-27-0Relevant articles and documents
Naphthalene and pyrrole substituted guanidine in selective sensing of Cu2+, Hg2+, Pb2+ and CN? ions under different conditions
Panja, Santanu,Chattopadhyay, Asoke P.,Ghosh, Kumaresh
, p. 528 - 535 (2017)
Naphthalene and pyrrole substituted guanidine 1 has been designed and synthesised. Compound 1 efficiently distinguishes Cu2+, Hg2+ and Pb2+ ions by exhibiting different responses in fluorescence. While compound 1 exhibited turn-on emission selectively in the presence of Hg2+ and Pb2+ ions in CH3CN and CH3CN–H2O (1:1, v/v), respectively, it showed decrease in emission upon interaction with Cu2+ ion in CH3CN. Furthermore, the Cu-1 ensemble has been established as a potential probe for selective detection of CN? ion over a series of other anions involving colour change (in ordinary light: colourless to light yellow and under UV light: colourless to sky blue). Theoretical insight has been invoked to understand the mode of metal–ligand interaction.
Carboxylate Binding by 2-(Guanidiniocarbonyl)pyrrole Receptors in Aqueous Solvents: Improving the Binding Properties of Guanidinium Cations through Additional Hydrogen Bonds
Schmuck, Carsten
, p. 709 - 718 (2007/10/03)
A series of guanidiniocarbonyl pyrrole receptors has been synthesized which bind carboxylates by ion pairing in combination with multiple hydrogen bonds. Their binding properties with various carboxylates have been investigated using NMR titration studies in 40% water/DMSO (ν/ν). The best receptor has association constants which are in the order of K ≈ 103 mol-1 and hence some 30 times larger than with the simple acetyl guanidinium cation. Through a systematic variation of the receptor structure, semiquantitative estimates for the energetic contributions of the individual binding interactions could be derived. These data show that the various hydrogen bonds are not equally important for the binding but differ significantly in their energetic contribution to the overall complexation process. Furthermore, the receptor can be made chiral and shows selectivity upon binding of enantiomeric amino acid carboxylates. Molecular modeling was used to obtain structural information for the various receptor carboxylate complexes and served as a basis to explain the observed differences in binding constants.