18457-95-9Relevant articles and documents
Direct photoreduction and ketone-sensitized reduction of nitrospirobenzopyranindolines by aliphatic amines
Goerner, Helmut
, p. 8208 - 8215 (2011)
The photoreduction of 6-nitrospiro[2H-1-benzopyran-2,2′-indoline] (N1) and two derivatives (N2 and N3) by diethylamine or triethylamine (TEA) in solution was studied by pulsed and steady-state photolysis. The quantum yield of coloration of the ring-closed
Multi-functional electro-optical molecular device. The photoelectrochemical behavior of spirobenzopyrans in dimethylformamide
Zhi,Baba,Hashimoto,Fujishima
, p. 32 - 39 (1995)
The photoelectrochemical investigation of 1,3,3-trimethylspiro(2H-1-benzopyran-2,2′-indoline) (SP-0) and 1,3,3-trimethyl-6-nitrospiro(2H-1-benzopyran-2,2′-indoline) (SP-1) has been performed in a dimethylformamide (DMF) solution at room temperature and at
Reversible photo-switching interaction between spiropyrans and polymer pyridine residues in a solid polymer membrane
Suzuki, Takayuki,Oda, Norihisa,Tanaka, Toshiyuki,Shinozaki, Hiraku
, p. 1803 - 1807 (2006)
A solid membrane of poly(2-ethylhexyl methacrylate-co-vinylpyridine) containing photochromic 6′-nitrospiropyran was prepared. In the rubbery copolymer membrane (Tg = -9 °C), the merocyanine (MC) form of the spiropyran isomerized into the spiro (SP) form by thermal decay after irradiation with UV light. The resulting decay showed two types of first-order kinetics, fast and slow. The activation energy for slow decay in the copolymer membrane was about 4 kcal mol-1 higher than that of fast decay. Furthermore, the standard enthalpy (ΔH°) of reversible isomerization (SP MC) without photolysis in the copolymer membrane was negative, in contrast to positive ΔH° values obtained for a homopolymer membrane of poly(2-ethylhexyl methacrylate) and for a liquid pyridine solution of spiropyrans. It was deduced that some of MC molecules in the copolymer membrane were thermodynamically stabilized. Additionally, the stabilized MC form in the copolymer membrane emitted intense green fluorescence (λem = 570 nm), while the simple MC form in the homopolymer or pyridine solution showed weak red emission (λem = 620-630 nm). The green fluorescence of the copolymer membrane was photo-reversible. These results suggest the existence of a photo-switchable interaction between spiropyrans and polymer pyridine residues in the solid copolymer membrane. The Royal Society of Chemistry 2006.
Photochromism of a Surface-active Spirobenzopyran Moiety in Dioxane-Water Mixtures and Self-assembled Surfactant Aggregates
Drummond, Calum J.,Furlong, D. Neil
, p. 3613 - 3621 (1990)
The photochemical and physicochemical properties of 1'-hexadecyl-3',3'-dimethyl-6-nitrospiro (SP 16) in micellar self-assembled surfactant aggregates have been investigated.For comparison the properties of 1',3',3'-trimethy
Study on the Chemical Reaction of Spiropyran in Medium- and High-Density Fluids
Kimura, Y.,Takebayashi, Y.,Hirota, N.
, p. 11009 - 11013 (1996)
We have studied the thermal conversion of 1,3',3'-trimethyl-6-nitrospiro (6-nitro-BIPS) in trifluoromethane (CHF3) and nitrous oxide (N2O) from near-critical to liquid-like density regions.The rate constant decreases with in
A Raman spectroscopic study of merocyanine aggregates of a 15N-isotopomer of 6-Nitro-1′,3′,3′-trimethylspiro[2H-1-benzopyran-2,2′- indoline]. A direct evidence for the association through the NO2-bridges
Sato, Hiroyasu,Matsuzaki, Akiyoshi,Nishio, Satoru,Yoshimi, Motohiro,Yamamoto, Katsutoshi,Tomioka, Hideo
, p. 715 - 716 (1996)
A Raman spectroscopic study on large-sized merocyanine aggregates prepared by the irradiating a 15NO2-isotopomer of 6-nitro-1′,3′,3′-trimethylspiro[2H-1-benzopyran-2,2′- indoline] (6-nitro BIPS) with UV light in a cyclohexane solutio
Photocyclization of diarylethenes: The effect of imidazole on the oxidative photodegradation process
Zakharov,Lvov,Rostovtseva,Metelitsa,Chernyshev,Krayushkin,Yadykov,Shirinian
, p. 1101 - 1109 (2019/05/24)
We have studied the photoreaction of 1,2-diarylethenes under aerobic conditions in the presence of various amines to prevent side processes promoted by singlet oxygen. It has been found that the most amines quite effectively deactivate processes associated with singlet oxygen, but primary and secondary amines unlike tertiary ones, react with substrates resulting in various side products. Among the studied amines, the most effective additive for preventing side processes, including those associated with singlet oxygen is imidazole, which is practically not consumed in photoreaction. It was shown that imidazole can also prevents the photodegradation of organic photochromes in solutions. The results obtained can be used in various branches of science, technology and medicine to improve the photostability of photosensitive organics (dyes).
Proton-Stabilized Photochemically Reversible E/ Z Isomerization of Spiropyrans
Kortekaas,Chen,Jacquemin,Browne
, p. 6423 - 6430 (2018/06/08)
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.
Nanosecond laser flash photolysis of a 6-nitroindolinospiropyran in solution and in nanocrystalline suspension under single excitation conditions
Breslin, Vanessa M.,Barbour, Nicole A.,Dang, Duy-Khoi,Lopez, Steven A.,Garcia-Garibay, Miguel A.
, p. 741 - 749 (2018/06/21)
Nanosecond transient absorption spectroscopy was used to study the photochemical ring-opening reaction for a 6-nitroindolinospiropyran (SP1) in solution and in nanocrystalline (NC) suspension at 298 K. We measured the kinetics in argon purged and air saturated acetonitrile and found that the presence of oxygen affected two out of the three components of the kinetic decay at 440 nm. These are assigned to the triplet excited states of the Z- and E-merocyanines (3Z-MC? and 3E-MC?). In contrast, a long-lived growth component at 550 nm and the decay of a band centered at 590 nm showed no dependence on oxygen and are assigned, respectively, to the ground state Z- and E-merocyanines (Z-MC0 and E-MC0). Laser flash photolysis studies performed in NC suspensions initially showed a very broad, featureless absorption spectrum that decayed uniformly for ca. 70 ns before revealing a more defined spectrum that persisted for greater than 4 ms and is consistent with a mixture of the more stable Z- and E-MC0 structures. We performed quantum mechanical calculations on the interconversion of E- and Z-MCs on the S0 and S1 potential energy surfaces. The computed UV-vis spectra for a scan along the Z → E interconversion reaction coordinate show substantial absorptivity from 300-600 nm, which suggests that the broad, featureless transient absorption spectrum results from the contribution of the transition structure and other high-energy species during the Z to E isomerization.
A study of the spiropyran-merocyanine system using ion mobility-mass spectrometry: Experimental support for the cisoid conformation
Rogers, Robert A.,Rodier, Allison R.,Stanley, Jake A.,Douglas, Nick A.,Li, Xiaopeng,Brittain, William J.
supporting information, p. 3424 - 3426 (2014/03/21)
The spiropyran-merocyanine system was studied using ion mobility-mass spectrometry (IM-MS) and three major conformers were identified. Assignment of conformers is based on DFT-B3LYP energy minimized structures and collision cross-sections as light-induced changes in IM-MS. The three conformers were assigned to the spiropyran, cisoid and transoid structures.
