The selectivity and sensitivity of N,N'-bis(4-diethylaminosalicylidene) hydrazine (sensor 1) toward Cu2+ ion have been established both by distinct "naked-eye" color change as well as UVvis spectrophotometry. Sensor 1 formed 1:1 complex with Cu2+ ion where the most stable s-trans form of the sensor is trapped in the high energy conformer. Single-crystal X-ray structure of sensor 1 supports its s-trans conformation. Theoretical calculations support well the experimental result. © 2011 The Chemical Society of Japan.

NIKHIL GUCHHAIT

Chemistry

S DALAPATI

S JANA

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Chemistry Letters

Realistically designed bis(indolyl)methanes from β-chloro-α,β-unsaturated aldehydes exhibited remarkable naked eye sensitivity towards Cu2+ ion. A green one pot technique has been developed for their synthesis using PMA-Cellulose as a reusable solid acid support/catalyst under solvent free condition. The procedure offered excellent yields within a short period of time. © 2015 Royal Society of Chemistry.

RSC Advances

An efficient solvent-free synthesis of bis(indolyl)methane-based naked eye chemosensor for Cu2+ ion from Î²-chloro-Î±,Î²-unsaturated aldehydes using PMA-Cellulose as a solid phase reusable catalyst

A simple Schiff base compound 2-((cyclohexylmethylimino)-methyl)-naphthalen-1-ol (2CMIMN1O) has been synthesized and characterized by 1H NMR, 13C NMR and FT-IR spectroscopic techniques. A significantly low emission yield of the compound has been rationalized in anticipation with photo-induced electron transfer (PET) from the imine receptor moiety to the naphthalene fluorophore unit. Consequently, an evaluation of the transition metal ion-induced modification of the fluorophore-receptor communication reveals the promising prospect of the title compound to function as a chemosensor for Cu2+ and Zn2+ ions selectively, through remarkable fluorescence enhancement as well as visual changes. While perturbation of the PET process has been argued to be the plausible mechanism behind the fluorescence enhancement, the selectivity for these two metal ions has been interpreted on the grounds of an appreciably strong binding interaction. Particularly notable aspects regarding the chemosensory activity of the compound is its ability to detect the aforesaid transition metal ions down to the level of micromolar concentration (detection limit being 2.74 and 2.27 ppm respectively), along with a simple and efficient synthetic procedure. © 2015 Elsevier B.V.

Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

Selective fluorescence sensing of Cu(II) and Zn(II) using a simple Schiff base ligand: Naked eye detection and elucidation of photoinduced electron transfer (PET) mechanism

A molecule having ethylenediamine unit with symmetrically attached aromatic frames has been synthesized, characterized and reported as a highly selective and sensitive chemosensor for Zn 2+ and Cd 2+ ion. UV-vis absorption and fluorescence emission spectra, quantum yield calculation, fluorescence lifetime measurement and the observed stability constant of metal-sensor complex support 1:1 complex formation for both Zn 2+ and Cd 2+ ion with the sensor. Enhancement of large Stokes shifted (130 nm for Zn 2+, 103 nm for Cd 2+) and polarity dependent emission bands were observed for Zn 2+ and Cd 2+ ions, while other transition metal ions Cr 3+, Fe 2+, Ni 2+, Co 2+, Cu 2+, Hg 2+ quench the fluorescence emission of the sensor. Ratiometric displacement of Cd 2+ ion from the complex by Zn 2+ ion supports the formation of more stable sensor-Zn 2+ complex over the sensor-Cd 2+ complex. Scanning electron micrographs show different structural morphology of the complexes. The experimental findings have been correlated with theoretical results using B3LYP functional and 6-311++G(d,p), LANL2DZ basis set for sensor and metal ion, respectively, by Density Functional Theory (DFT) method. © 2012 Elsevier B.V.

Journal of Photochemistry and Photobiology A: Chemistry

Fluorescent chemosensor for Zn(II) ion by ratiometric displacement of Cd(II) ion: A spectroscopic study and DFT calculation

Three new trinuclear copper(II) complexes, [(CuL1) 3(μ3OH)][ClO4]23H2O (1), [(CuL2)3(μ3-OH)][ClO4] 2H2O (2), and [(CuL3) 3(μ3-OH)][ClO4]27H2O (3) have been synthesized from the three tridentate Schiff bases HL1, HL2, and HL3 (HL1 = 6aminomethyl-3-methyl-1- phenyl-4-azahex-2-en-1-one, HL2 = 6-aminoethyl-3methyl-1 -phenyl-4-azahex-2-en-1 -one, and HL3 = 6-aminodimethyl-3-methyl1- phenyl-4-azahex-2-en-1-one). They have been characterized by X-ray crystallography and IR and UV spectroscopy, and their magnetic properties have been investigated. All the compounds contain a partial cubane [Cu 3O4] core consisting of the trinuclear unit [(CuL) 3(μ3-OH)]2+, Perchlorate ions, and water molecules. In each of the complexes, the copper atoms are fivecoordinate with a distorted square-pyramidal geometry except complex 1, in which one of the CuII of the trinuclear unit is weakly coordinated to one of the Perchlorate ions. Magnetic measurements performed in SQUID MPMS-XL7 using polycrystalline samples at an applied field of 2 kOe indicate a global intramolecular ferromagnetic coupling. Magnetostructural correlations have been calculated on the basis of theoretical models without symmetry restriction. Continuous shape measurements are an appropriate tool for establishing the degree of distortion of the CuII from squareplanar geometry. Structural, theoretical, and experimental magnetic data indicate that the higher the degree of distortion, the greater the ferromagnetic coupling. © 2007 Wiley-VCH Verlag GmbH &amp; Co. KGaA.

Journal	Chemistry Letters
Publisher	CHEMICAL SOC JAPAN
ISSN	0366-7022
Open Access	No