1485-92-3

Usage

Uses

Used in Eyewear Industry:
1,3,3-Trimethylindolinobenzopyrylospiran is used as a photochromic material for the production of color-changing lenses. Its ability to transition from colorless to colored upon exposure to UV light provides eye protection and comfort to users in varying light conditions.
Used in Camera Filters Industry:
1,3,3-Trimethylindolinobenzopyrylospiran is used as a photochromic component in camera filters. Its unique property of changing color upon exposure to UV light allows for dynamic adjustment of light transmission, enhancing image quality and performance in different lighting environments.
Used in Optical Data Storage:
1,3,3-Trimethylindolinobenzopyrylospiran has potential applications in optical data storage due to its reversible photochromic behavior. This property can be utilized to encode and decode information in optical storage media, offering a novel approach to data storage technology.
Used as a Light Intensity Sensor:
1,3,3-Trimethylindolinobenzopyrylospiran can be employed as a sensor for light intensity. Its color change in response to UV light can be measured and correlated to the intensity of the light source, providing a means to detect and monitor light levels in various applications.

Upstream product

• 118-12-7 1,3,3-Trimethyl-2-methyleneindoline 
• 90-02-8 salicylaldehyde 
• 78844-66-3 1,3,3-trimethyl-2-(2-buten-1-ylidene)indoline 
• 64-17-5 ethanol 
• 7664-41-7 ammonia 
• 7732-18-5 water 
• 89-95-2 2-methyl-benzyl alcohol 
• 2016-67-3 6-[2-(1,3,3-trimethyl-2,3-dihydro-1H-indol-2-ylidene)ethylidene]-2,4-cyclohexadienone 
• 5418-63-3 1,2,3,3-tetramethyl-3H-indolium iodide 

Relevant academic research and scientific papers

Improving the synthesis of spiropyran derivatives using microwave irradiation method

A solvent free synthesis of spiropyran derivatives has been developed from the condensation of indoline and salicylaldehyde using a microwave irradiation method. This method starts from readily available starting materials and provides biologically interesting products. The microwave irradiation method was remarkably successful and gave spiropyran derivatives in higher yield (72-99%) with a much shorter reaction time (10-15 min) compared to the conventional heating method. The chemical structures of the compounds prepared were characterized through IR, 1H NMR and 13C NMR spectral data.

Thermal racemization of substituted indolinobenzospiropyrans: Evidence of competing polar and nonpolar mechanisms

A series of 6-substituted indolinobenzospiropyrans were resolved by chiral stationary phase HPLC and rate constants k(rac) for their thermal racemization were measured by circular dichroism spectropolarimetry at 60 °C in three different solvents: cyclohexane, 90:10 hexanes/2-propanol, and acetonitrile. Results show that the spiropyrans undergo thermal racemization most rapidly in acetonitrile, with k(rac) values ranging from 9.3 x 10 -5 to >5.0 x 10 -3 s -1, and least rapidly in cyclohexane, with k(rac) values ranging from 6.8 x 10 -6 to 4.6 x 10 -4 s -1. V-shaped plots of log k(rac) vs Hammett σ(p) constants in 90:10 hexanes/2-propanol and acetonitrile suggest that thermal racemization of the 6-substituted spiropyrans proceed via two competing mechanisms: a polar mechanism involving heterolytic C(sp3)-O bond cleavage with anchimeric assistance from the indoline nitrogen and a nonpolar electrocyclic ring opening mechanism with no anchimeric assistance from the indoline nitrogen. The outcome of this competition appears to be strongly influenced by solvent polarity: plots of log k(rac) vs σ(p) and σ- in cyclohexane show a near-linear correlation with negative slope, which is consistent with the nonpolar mechanism. However, an increase in solvent polarity results in a shift toward a linear correlation with positive slope, which is consistent with the polar mechanism.

Proton-Stabilized Photochemically Reversible E/ Z Isomerization of Spiropyrans

Spiropyrans undergo Cspiro-O bond breaking to their ring-open protonated E-merocyanine form upon protonation and irradiation via an intermediate protonated Z-merocyanine isomer. We show that the extent of acid-induced ring opening is controlled by matching both the concentration and strength of the acid used and with strong acids full ring opening to the Z-merocyanine isomer occurs spontaneously allowing its characterization by 1H NMR spectroscopy as well as UV/vis spectroscopy, and reversible switching between Z/E-isomerization by irradiation with UV and visible light. Under sufficiently acidic conditions, both E- and Z-isomers are thermally stable. Judicious choice of acid such that its pKa lies between that of the E- and Z-merocyanine forms enables thermally stable switching between spiropyran and E-merocyanine forms and hence pH gating between thermally irreversible and reversible photochromic switching.

New stable colored complex of Al3+ with 1',3',3'-trimethylspiro[2H-1-benzopyran-2,2'-indoline] (BIPS)

Ultraviolet-visible (UV-vis) absorption, flash photolysis, and 1H and 13C NMR spectroscopy were used to investigate the mechanism of formation and structure of complexes in the 1',3',3'-trimethylspiro[2H-1-benzopyran-2,2'-indoline] (SP, also well known as BIPS) with Al3+ (inorganic salts) in ethanol (EtOH), methanol (MeOH), and in aqueous MeOH solutions. A labile (equilibrium constants ≤ 5000 M?1) complex of SP and Al3+ with broad absorption band in the UV-vis with λmax = 380 nm appeared promptly in the presence of an excess of Al3+. The slow formation of a stable complex (SC) between Al3+ and two merocyanine (MC) forms of SP with an intensive absorption band at λmax = 430 nm is observed with a yield of 1.0 upon keeping the solutions of these two compounds at constant concentration ratio [Al3+] ≥[SP]/2 in the dark. The rate constants of such SC formation were close to the corresponding rate constant of the transformation of SP into MC in the dark (5.0×10?5-1×10-3 s-1, depending upon the solvent). The photolysis of the SC with visible light (λ > 400 nm) results in the total conversion of the SC into SP. The SC forms promptly after the addition of Al3+ at concentrations of the same order as those of MC. This method allows detection of [Al3+] to concentrations as low as 50 nM. The kinetics and thermodynamic parameters of the SP and MC reactions and of their complex formation with Al3+ are discussed.

'Ship-in-a-bottle' synthesis and photochromism of spiropyrans encapsulated within zeolite Y supercages

The ship-in-a-bottle synthesis of three spiropyrans inside the NaY supercages was carried out by the condensation of 2-methylene-1,3,3-trimethylindoline with the appropriate substituted benzaldehyde. After the reaction, spiropyrans were detected in the supernatant and the zeolites became coloured. Combustion chemical and thermogravimetric analyses confirmed the presence of organic material within the solid. UV-Vis and Raman spectroscopies are compatible with the formation of the merocyanine form of the spiropyran photochromic system. Upon visible irradiation the solids bleach, and in some cases the coloration is regained upon standing in the dark for long periods. This abnormal photochromic behaviour is the reverse of that observed for the spiropyran/merocyanine system in ethanol and illustrates the possibility of zeolites as media to alter the molecular properties of incorporated guests. (C) 2000 Elsevier Science Ltd.

Thermo- and Photochromic Dyes: Spiro(indolinebenzopyrans) 2. - Detailed Assignment of the 1H NMR Spectra and Structural Aspects of the Closed Form of 1,3,3-Trimethylspiro(indoline-2,2'-benzopyrans)

The proton NMR assignments for a series of 12 thermo- and photochromic 1,3,3-trimethylspiro(indoline-2,2'-benzopyrans) dyes is reported.All of the protons in the dye molecule were assigned through a combination of homonuclear decoupling experiments and correlation spectroscopy.The relative stereochemistry of the indolino gem-dimethyl groups was assigned so that, for the S-epimer, the pro-R methyl was found to resonate at 1.24 ppm while the pro-S methyl appeared at 1.37 ppm for compound 1. KEY WORDS: Thermo- and photochromic dyes, Spiro(indoline-2,2'-benzopyrans), 1H NMR assignments

Synthesis, optical properties and in vitro cell viability of novel spiropyrans and their photostationary states

A novel class of spiropyran (SP) was synthesized using a multistep process that involves three key intermediates: (a) diazonium-tetrafluoroborate, (b) hydrazine and (c) indolium iodide. Single crystal X-ray spectroscopy was used to confirm the structure of one of the analogues. The SP analogues were confirmed as being able to isomerize and attain a photostationary state (PSS) upon irradiation with ultraviolet light (UV, 365 nm) in an aqueous environment. UV–visible absorption spectra were recorded to confirm the isomerization properties. The ability of the synthesized compounds to induce growth inhibition of HeLa cervical cancer cells was assessed via the MTT assay after incubation with either the SP or their PSS. The IC50 values of two PSS (PSS-2, 4), were observed to be around 14 ± 4 fold lower (26 ± 3 μM) than their corresponding SPs. The most cytotoxic compounds SP-7 and PSS-7 showed the lowest IC50 values (12 μM). An in vitro tubulin polymerization assay showed that SP-7 and PSS-7 exhibited the greatest difference in tubulin inhibition relative to unirradiated SP-1 and SP-4.

Sublimation thermodynamics of indoline and benzoxazine based spiropyrans

Sublimation of 1,3,3,6′-tetramethyl-8′-formyl-spiroindoline-2,2′-[2H] -chromene (SP-1) and 3,6′-dimethyl-8′-formyl-spiro (4-oxo-3,4-dihydro-2H-1,3-benzoxazine)-2,2′-[2H] -chromene (SP-2) was studied by Knudsen effusion mass spectrometry in the temperature range 309–363 K and 331–384 K, respectively. It has been shown that, in the temperature range under study, both spiropyrans are thermally stable and sublime congruently in the form of monomeric molecules. The dependences of the saturated vapor pressure (Pa) on temperature are described by the equations: lg p (SP-1) = – (6.239±0.093)?103?T–1+ (15.832±0.278), lg p (SP-2) = – (6.625±0.111)?103?T–1 + (15.459±0.312). The sublimation enthalpies have been evaluated by the second law method as ΔsH°(298.15 K) = 119±5 kJ?mol–1 (SP-1) and ΔsH°(298.15 K) = 128±5 kJ?mol–1 (SP-2). The enthalpies of formation of spiropyran molecules in the ideal gas state, ΔfH°g(298.15 K) = 199±9 kJ?mol–1 (SP-1) and ΔfH°g(298.15 K) = –296±10 kJ?mol–1 (SP-2), have been calculated using isodesmic reactions method implying quantum chemical calculations. Combining the latter values with the corresponding sublimation enthalpies the enthalpies of formation for crystalline state spiropyrans were determined: ΔfH°cr(298.15 K) = 80±10 kJ?mol–1 (SP-1) and ΔfH°cr(298.15 K) = –424±11 kJ?mol–1 (SP-2).

Spiropyrans and spirooxazines and preparation method thereof

The invention provides spiropyrans, naphthospiropyrans and spirooxazines. The invention also relates to a method for preparing the spiropyrans, the naphthospiropyrans and the spiroxazines by reactionof indole compounds, especially indole iodide, with alde

Greener route for the synthesis of photo- and thermochromic spiropyrans using a highly efficient, reusable, and biocompatible choline hydroxide in an aqueous medium

Here, we report the synthesis of photo- and thermochromic spiropyrans promoted by a highly efficient, biocompatible, and reusable choline hydroxide (ChOH) in greener solvent water. This procedure provides several advantages such as simple workup, mild reaction conditions, short reaction time, and high yields of the products. Furthermore, the ChOH could be reused at least five times without significantly losing its catalytic activity. The structures of the synthesized spiropyran derivatives were confirmed by several characterization methods such as 1H NMR, 13C NMR, and mass spectra.