23302-83-2

Basic information

• Product Name: MEROCYANINE DYE
• Synonyms: Brooker's merocyanine dye;4-[2-(1-methyl-1,4-dihydropyridin-4-ylidene)ethylidene]cyclohexa-2,5-dien-1-one;4-(2-(1-METHYLPYRIDIN-4(1H)-YLIDENE)ETHYLIDENE)CYCLOHEXA-2,5-DIEN-1-ONE
• CAS NO: 23302-83-2
• Molecular Formula: C₁₄H₁₃NO
• Molecular Weight: 211.25912
• Mol File: 23302-83-2.mol

Chemical Properties

• Melting Point: 220℃
• Boiling Point: 360.6°Cat760mmHg
• Flash Point: 141.5°C
• Appearance: /
• Density: 1.268g/cm³
• Vapor Pressure: 2.19E-05mmHg at 25°C
• Refractive Index: 1.752
• PKA: 4.41±0.20(Predicted)
• CAS DataBase Reference: MEROCYANINE DYE(CAS DataBase Reference)
• NIST Chemistry Reference: MEROCYANINE DYE(23302-83-2)
• EPA Substance Registry System: MEROCYANINE DYE(23302-83-2)

Safety Data

• Hazardous Substances Data: 23302-83-2(Hazardous Substances Data)

Usage

Uses

Used in Chemical Analysis:
MEROCYANINE DYE is used as a solvent polarity indicator for determining the polarity of different solvents. Its color change in response to variations in solvent polarity allows for easy identification and classification of solvents based on their polarity.
Used in Environmental Monitoring:
MEROCYANINE DYE is used as a pH sensor for monitoring changes in pH levels in various environments. Its sensitivity to pH variations makes it an ideal tool for detecting and measuring changes in acidity or alkalinity in solutions, which is crucial in various fields such as water quality assessment, agriculture, and industrial processes.
Used in Analytical Chemistry:
MEROCYANINE DYE is used as a transition metal cation indicator in analytical chemistry. Its ability to change color in the presence of specific metal cations makes it a valuable tool for detecting and identifying metal ions in samples, which is essential in various applications such as metal ion analysis, environmental monitoring, and quality control in the chemical industry.

InChI:InChI=1/C14H13NO/c1-15-10-8-13(9-11-15)3-2-12-4-6-14(16)7-5-12/h2-11H,1H3

Upstream product

• 2301-80-6 N-methyl-4-methylpyridinium iodide 
• 123-08-0 4-hydroxy-benzaldehyde 
• 95495-28-6 1-methyl-4-[2-(4-hydroxyphenyl)ethenyl]pyridinium iodide 
• 67106-77-8 (E)-4-[2-(1-methylpyridinium-4-yl)ethenyl]phenolate 
• 23302-83-2 4-[(1-methyl-4(1H)-pyridinylidene)-ethylidene]-2,5-cyclohexadiene-1-one 
• 67106-80-3 cis-1-methyl-4-(4'-hydroxystyryl)pyridinium betaine 

Downstream Products

• 67106-77-8 (E)-4-[2-(1-methylpyridinium-4-yl)ethenyl]phenolate 
• 1070163-74-4 1-methyl-4-[2-(4-hydroxyphenyl)ethenyl]pyridinium hydrogensquarate 
• 1163686-35-8 C₁₄H₁₃NO*C₄₂H₇₀O₃₅ 
• 67106-80-3 cis-1-methyl-4-(4'-hydroxystyryl)pyridinium betaine 

Relevant articles and documents

Complexes of carboxylato pillar[6]arene with Brooker-type merocyanines: Spectral properties, pKa shifts and the design of a displacement assay for trimethyl lysine

The supramolecular complexes of three strongly solvatochromic dyes, Brooker's merocyanine (M1) and its two derivatives (M2, M3) with carboxylato pillar[6]arene (WP6) were studied in aqueous solutions. The dye-WP6 mixtures were described in terms of four equilibrium reactions: the acidic dissociations of the pyridinium phenols into the zwitterionic phenolates, the acidic dissociations of the complexed phenols, the bindings of the phenol form dyes to WP6 and the bindings of the phenolates to WP6. The equilibrium constants were determined by an analysis of the absorption spectra. It was found that the acidity of the phenol form merocyanines were largely reduced on complexation, pKa shifts of 1.1–1.6 units were observed. In neutral solutions, the complexes of the phenol forms of M1 and M2 were dominant, in contrast to the more acidic M3 (a dibromo derivative), of which the phenolate complex was more stable. Comparing the spectral properties, the binding constants and the pKa-s of the dye-WP6 complexes, the complex M3?WP6 was chosen to be tested as a displacement assay. It was demonstrated that this complex functioned as a colorimetric indicator displacement assay which discriminated trimethyl lysine from other lysine derivatives.

The aggregation of the merocyanine dyes, depending of the type of the counterions

Counterions affect on the substructures formation in the case of the merocyanine dye, 1-methyl-4-[2-(4-hydroxyphenyl)ethenyl)]piridinium] hydrogensquarate both in gas and condense phase. Spectroscopically and structural elucidation of these aggregates have been performed, using solid-state conventional and linear-polarized IR-spectroscopy of oriented colloids as a nematic liquid crystal suspension, UV-vis spectroscopy, HPLC tandem ESI mass spectrometry, 1H and 13C NMR, TGV and DSC. Quantum chemical DFT calculations have been carried out as well. Experimental and theoretical data are compared with analogous ones of corresponding iodide salt of dye studied.

Isomerizable N-Alkylmerocyanine Dyes as Probes of Micellar Solubilization Sites

The thermal cis to trans isomerization of N-alkylmerocyanine dyes is catalyzed by both cationic and anionic micelles.The catalysis by cationic micelles of hexadecyltrimethylammonium bromide (CTABr) increases markedly with substrate N-alkyl group length and is exceptionally pronounced for N-alkyl groups larger than pentyl.Rate data fit the pseudophase model of micellar catalysis for CTABr concentrations between 0.005 and 0.1 M and binding constants (KS) and micellar rate constants (km) were evaluated.Both KS and kmincreased dramatically as the N-alkyl group was varied from N-methyl to N-pentyl so that the increase in catalysis with substrate hydrophobicity is due not only to increased substrate binding to the micelle but also to enhanced reactivity within the micelle.At CTABr concentrations greater than 0.1 M, km is not constant but increases, reflecting changes in micelle structure at bigh surfactant concentration.Eyring activation parameters were determined for the overall rate constant.The increase in reactivity as a function of N-alkyl group hydrophobicity was shown to be due primarily to an increase in ΔS.

Thermal Cis-Trans Isomerization of Solvatochromic Merocyanines: Linear Correlations between Solvent Polarity and Adiabatic and Diabatic Transition Energies

The correlation between solvatochromy and the sovent-polarity-dependent rate constant kct of thermal cis-trans isomerization (solvatokinetic behavior) has been investigated for a stilbazolium-type merocyanine and an amphiphilic analogue in a polarity series of eight neat solvents (protic and aprotic).At room temperature kct varies over 7 orders of magnitude, decreasing with increasing solvent polarity.It has been demonstrated that the first transition energy ΔEmax and the free activation enthalpy ΔG(excit.)ct of thermal cis-trans isomerization are linearly correlated with each other and with Dimroth's solvent polarity parameter ET.These observations and the sovent-polarity-dependent increase of absorption band width are explained in terms of a model emphasizing the strong coupling between molecular conformation, electronic charge distribution, and solvent polarization.

Korrelation zwischen loesungsmittelinduzierten Elektronenstrukturaenderungen und kinetischen Parametern der thermischen cis-trans-Isomerisierung bei negativ solvatochromen Merocyaninen

The kinetic parameters of the thermally induced cis-trans-isomerisation of negatively solvatochromic dye; 4(4'-hydroxystyryl)-N-methylpyridinium betain have been spectrophotometrically determined as a function of solvent polarity parameter (ET-value).The parameters A, EA and ΔS* increase with increasing solvent polarity.This effect is attributed to an increase of the twisting angle of the cis-form and to the solvent induced structural changes from a polymethine-like state in nonpolar solvents to a polyene-like state in polar solvents, where the ?-bond character of the ethene C=C-bond is increased.

A Quantitative Description of Polarity of Binary Solvent Mixtures Using Different Polarity Scales

The solvent polarities of 12 binary mixtures have been examined using 6 polarity scales as a function of their composition.They are quantitatively described by a simple, closed form, two-parameter equation which can explain e.g. deviations from linear correlations of polarity scales for mixtures.