We report the synthesis of a novel hydrazine based compound 1-[(2-Hydroxy-1, 2-diphenyl-ethyl)-hydrazonomethyl]-naphthalen-2-ol (2). Compound 2 is the first report of its kind. We utilized the aforesaid compound to detect Cu2+ and F− via emission enhancement and naked eye color change. The structural intricacies of 2 have been explored by its crytal structure. The mechanism of binding of 2 with F− has been established by 1H NMR titration. The limit of detection for Cu2+ and F− is ∼9.0 × 10−7 (M) and 1.0 × 10−6 (M), respectively. The practical performance of 2 is demonstrated by successful live cell imaging of Cu2+ and detection of F− in toothpaste. © 2017 Elsevier B.V.

NIKHIL GUCHHAIT

Chemistry

A BHATTACHARYYA

S GHOSH

S C MAKHAL

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

Journal of Photochemistry and Photobiology A: Chemistry

We report the synthesis and photophysical properties of a coumarin based probe (1E)-1-(1-(7-(diethylamino)-2-oxo-2H-chromen-3-yl) ethylidene) thiosemicarbazide (DIDOT). DIDOT shows a polarity dependent change in the emission maxima in the solution phase. This is explained by the increased dipole moment in the excited state by an intramolecular charge transfer (ICT) process. DIDOT can successfully detect Zn(ii) in aqueous methanol by a shift in the charge transfer emission maxima from approximately 506 to approximately 535 nm. This shift led to a change in the color of the emission from green to yellow under UV-light. The mechanism of Zn(ii) detection has been delineated using electrospray ionization-mass spectrometry (ESI-MS), Fourier-transform infrared spectroscopy (FTIR) and fluorescence time resolved studies coupled with theoretical calculations. The increment in the charge transfer in the Zn(ii) complex of DIDOT over the bare receptor as a consequence of conformational locking was determined to be the underlying cause of the cation detection phenomenon. The limit of detection and binding constant values of DIDOT towards Zn(ii) were approximately 3 × 10-8 M and 2.35 × 105 M-1 respectively. Finally, the practical utility of DIDOT has been demonstrated by successful detection and quantification of Zn(ii) in spiked water samples. © 2019 The Royal Society of Chemistry and Owner Societies.

Photochemical and Photobiological Sciences

Evaluating the merit of a diethylamino coumarin-derived thiosemicarbazone as an intramolecular charge transfer probe: Efficient Zn(II) mediated emission swing from green to yellow

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

Sensor 1 (a Schiff base) obtained by the condensation of 4-nitro-o-phenyldiamine and 2-hydroxy-1-naphthaldehyde can detect fluoride ion selectively through visual color change. Moreover, insitu cyclisation of sensor 1 to benzimidazole derivative 2 takes place by the help of fluoride ion as evidenced by X-ray crystal structure. The crystal structures of the sensor 1 and benzimidazole derivative 2 show that several types of weak C-H...X (X = O, N), C-H...π and π...π interactions play a crucial role along with intra/inter molecular H-bonding interactions for the stabilization of crystal lattice. © 2015 Elsevier B.V. All rights reserved.

Inorganica Chimica Acta

Selective colorimetric sensing of fluoride ion and its use for insitu cyclization of the sensor

A novel fluorescent chemosensor based on a rhodamine derivative (L) was designed, synthesized, and used as a selective Al+3 ion sensor. Upon addition of Al3+ to an aqueous-acetonitrile solution of L, the development of a strong fluorescence signal by a chelation-enhanced fluorescence (CHEF) process was observed with an attractive glowing orange emission. This sensor shows high selectivity towards Al3+ ions in the presence of other competing metal ions. The fluorescence quantum yield of L-Al3+ (Φf = 0.30) was found to be very high compared to the bare ligand. The limit of detection (LOD) of Al3+ ions was calculated to be 2 × 10-8 M by fluorescence titration. The 1 : 1 binding stoichiometry of the metal complex was established by combined UV-vis, fluorescence and TOF-MS spectroscopy. © 2014 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

New Journal of Chemistry

Rhodamine-based molecular clips for highly selective recognition of Al 3+ ions: Synthesis, crystal structure and spectroscopic properties

A new Schiff base compound 2-((benzylimino)-methyl)-naphthalen-1-ol (2BIMN1O) has been synthesized and characterized by 1H NMR, 13C NMR, DEPT, FT-IR and mass spectroscopic techniques. The significantly low fluorescence yield of the compound has been rationalized in connection with photo-induced electron transfer (PET) from the imine receptor moiety to the naphthalene fluorophore unit. Subsequently, an evaluation of the transition metal ion-induced modification of the fluorophore-receptor communication reveals a promising prospect for the title compound to function as a fluorosensor for Cu2+ and Zn2+ ions selectively, through remarkable fluorescence enhancement. While perturbation of the PET process in 2BIMN1O has been argued to be the responsible 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 are its ability to detect the aforesaid transition metal ions down to the level of micromolar concentration (detection limit being 0.82 and 0.35 μM respectively), along with a simple and efficient synthetic procedure. Also the spectral modulation of 2BIMN1O in the presence of the transition metal ions paves the way for the construction of a calibration curve in the context of its fluorescence signaling potential. © 2013 The Royal Society of Chemistry.

Analyst

Selective fluorescence sensing of Cu(ii) and Zn(ii) using a new Schiff base-derived model compound: Naked eye detection and spectral deciphering of the mechanism of sensory action

Test paper coated with Schiff base [(N,N/-bis(5-nitro- salicylidene)hydrazine] receptor 1 (host) can selectively detect fluoride and acetate ions (guest) by developing yellow color which can be detected by naked-eye both in aqueous-acetonitrile solution and in solid supported test kit. UV-vis spectral analysis shows that the absorption peaks at 288 and 345 nm of receptor 1 gradually decrease its initial intensity and new red shifted absorption bands at 397 nm and 455 nm gradually appear upon addition of increasing amount of F- and AcO- ions over several tested anions such as H2PO4-, Cl-, Br-, I-, NO3-, NO2-, HSO4-, HSO3-, and ClO4- in aqueous-acetonitrile solvent. The colorimetric test results and UV-vis spectral analysis are in well agreement with 1H NMR titration results in d6-DMSO solvent. The receptor 1 forms 1:2 stable complexes with F- and AcO- ions. However, similar kind of observation obtained from UV-vis titrations in presence of AcOH corresponds to 1:1 complexation ratio indicating the formation of H-bonding interaction between the receptor and anions (F- and AcO- ions). So, the observed 1:2 complexation ratio can only be explained on the basis of deprotonation (∼1 eqv.) and H-bonding (∼1 eqv.) interactions [1]. The ratiometric analysis of host-guest complexes corroborates well with the proposed theoretical model optimization at Density Functional Theory (DFT) level. © 2012 Elsevier B.V. All rights reserved.

Test kit for detection of biologically important anions: A salicylidene-hydrazine based Schiff base

Hydrazine appended self assembled benzoin-naphthalene conjugate as an efficient dual channel probe for Cu2+ and Fâˆ’: A spectroscopic investigation with live cell imaging for Cu2+ and practical performance for fluoride

Journal	Data powered by TypesetJournal of Photochemistry and Photobiology A: Chemistry
Publisher	Data powered by TypesetElsevier B.V.
ISSN	1010-6030
Open Access	No