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Search for "bathochromic shift" in Full Text gives 109 result(s) in Beilstein Journal of Organic Chemistry.
Naphthalonitriles featuring efficient emission in solution and in the solid state
Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246
- in the cases of Me and t-Bu compounds, where a gradual bathochromic shift in emission is observed with growing water fraction (Figures S35 and S36, Supporting Information File 1), pointing to a slight charge-transfer character of the emissive state. These compounds show a prominent AIEE upon
Synthesis and characterization of S,N-heterotetracenes
Beilstein J. Org. Chem. 2020, 16, 2636–2644, doi:10.3762/bjoc.16.214
- only slightly red-shifted. The effect of benzannulation in 19 compared to H-SN4 13 as well results only in small differences, which, however, become larger in comparison to hexacyclic heteroacene 22 showing the largest bathochromic shift in the series (Figure S6, Supporting Information File 1). The
Recent developments in enantioselective photocatalysis
Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197
Styryl-based new organic chromophores bearing free amino and azomethine groups: synthesis, photophysical, NLO, and thermal properties
Beilstein J. Org. Chem. 2020, 16, 2282–2296, doi:10.3762/bjoc.16.189
- . The pH-sensitive properties of all prepared Schiff bases were examined against TBAOH in DMSO, via deprotonation of the OH group in the salicylidene moiety and their reverse protonation was also investigated using TFA. The Schiff bases exhibited a bathochromic shift upon the addition of TBAOH to their
- and 8 > 9 > 10 > 11 > 12 in DMSO, which was consistent with the experimental data (Table 1 and Table S1 in Supporting Information File 1). A solvent effect on the absorption spectra was observed for compound 4 resulting in a bathochromic shift of about 22 nm from PhMe to DMSO, whereas there was only a
Synthesis and highly efficient light-induced rearrangements of diphenylmethylene(2-benzo[b]thienyl)fulgides and fulgimides
Beilstein J. Org. Chem. 2020, 16, 1820–1829, doi:10.3762/bjoc.16.149
- bathochromic shift of the 441 nm band accompanied by a typical redistribution of intensity of absorption bands (see Table 1) is detected. At longer irradiation times, the rearrangement processes are reflected by the spectral curves depicted in Figure 3. Crystal packing of the product of the photoinduced
Et3N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties
Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146
- benzothiophenone derivatives exhibited better photophysical properties including high quantum yield, brightness and significant bathochromic shift in the emission wavelengths. In short, β-carboline-substituted benzothiophenone derivatives emerged as excellent fluorophores and displayed remarkable photophysical
Heterogeneous photocatalysis in flow chemical reactors
Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125
- nanoparticles) or by introducing impurities into the crystal lattice, otherwise known as doping [44][84][85][86]. Semiconductor doping adds additional filled or vacant quantum states to the band structure that lie within the band gap, reducing the Eg and typically resulting in a bathochromic shift in absorption
- via physisorption. However, functionalised molecules and ions can strongly bind through chemisorption by covalent bonds, hydrogen bonding, or electrostatic attraction and have been shown to influence the photophysical properties of TiO2, generally causing a bathochromic shift of the absorption
Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore
Beilstein J. Org. Chem. 2020, 16, 1111–1123, doi:10.3762/bjoc.16.98
- –vis spectra of oxazolones 2 show that the absorption is zero or close to zero. Therefore, the lack of reactivity of species 2 can be related with the absence of the absorption of light. However, the ortho-palladation causes a clear bathochromic shift from compounds 2 to 3 and this results in
A simple and easy to perform synthetic route to functionalized thienyl bicyclo[3.2.1]octadienes
Beilstein J. Org. Chem. 2020, 16, 1092–1099, doi:10.3762/bjoc.16.96
- that p-substituents (trans-3, trans-4, and trans-7) enabled a higher value of molar extinction coefficients, in comparison to o-substituted compounds (trans-5 and trans-6). The cyano-substituted compound trans-6 showed the largest bathochromic shift, in regards to the methyl and methoxy-substituted
Aryl-substituted acridanes as hosts for TADF-based OLEDs
Beilstein J. Org. Chem. 2020, 16, 989–1000, doi:10.3762/bjoc.16.88
- accompanied by intermolecular CT state relaxation. Such emission is evidenced by solvatochromic effects, i.e., a bathochromic shift of the emission peak due to the change of the environment to a more polar one. By replacement of the solvent toluene with THF, the solution of 4 exhibited a bathochromic shift of
Cation-induced ring-opening and oxidation reaction of photoreluctant spirooxazine–quinolizinium conjugates
Beilstein J. Org. Chem. 2020, 16, 904–916, doi:10.3762/bjoc.16.82
- photodegradation of the substrate (Figure S2A, Supporting Information File 1). For 3b, the irradiation at 420 nm led to a decrease of the absorption and a bathochromic shift of the long-wavelength absorption band, and after an irradiation time of 60 min, the spectrum showed distinct absorption bands with maxima at
Bipyrrole boomerangs via Pd-mediated tandem cyclization–oxygenation. Controlling reaction selectivity and electronic properties
Beilstein J. Org. Chem. 2020, 16, 895–903, doi:10.3762/bjoc.16.81
- . Pairs of lactam rings present in cNMI2O and cNMI3O form a quinoidal substructure, which produces a very significant bathochromic shift of their lowest-energy absorption bands (up to 176 nm in toluene) in comparison to the of α-unsubstituted analogues. Lactam bipyrroles cNDAnO and cNMInO show noticeable
Synthesis of triphenylene-fused phosphole oxides via C–H functionalizations
Beilstein J. Org. Chem. 2020, 16, 524–529, doi:10.3762/bjoc.16.48
- reflected the characteristics of PAHs including triphenylene derivatives (Table 1, entries 5 and 6) [32][33][34], rather than the 2,3-dialkylbenzo[b]phosphole core (Table 1, entry 4). As expected, the absorption of 8c showed a bathochromic shift compared to 8a and 8b as a result of π-extension (Table 1
Photophysics and photochemistry of NIR absorbers derived from cyanines: key to new technologies based on chemistry 4.0
Beilstein J. Org. Chem. 2020, 16, 415–444, doi:10.3762/bjoc.16.40
- helped to understand the function and formation H and J-aggregates [46][47][48][49] being aligned parallel or in series, respectively. The capability of cyanines to form J-aggregates exhibiting a huge bathochromic shift, which was reported for the first time by Scheibe [50] and Jelley in 1937 [51
- bathochromic shift of the absorption of about 100 nm [3]. Substitution of the terminal groups comprising by either substituted indolium, benzo[e]indolium or benzo[c,d]indolium patterns helps to finetune the absorption wavelength with respect to the light source used. Furthermore, different substituents at the
Six-fold C–H borylation of hexa-peri-hexabenzocoronene
Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37
- calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the σ-donation of boryl groups. Keywords: C–H borylation; hexa-peri-hexabenzocoronene; iridium catalyst; X-ray crystallography; Introduction Polycyclic aromatic hydrocarbons (PAHs
- its LUMO and LUMO+1 are degenerate. The HOMO and LUMO energies of 1 increase under the influence of the σ-donation of the boryl groups, resulting in a decrease of the HOMO–LUMO energy gap. This is in line with the bathochromic shift observed in the absorption spectrum of 1 from that of HBC. Conclusion
Potent hemithioindigo-based antimitotics photocontrol the microtubule cytoskeleton in cellulo
Beilstein J. Org. Chem. 2020, 16, 125–134, doi:10.3762/bjoc.16.14
- strength of groups in the hemistilbene para-position of HTIs correlates to (a) a bathochromic shift of the S0 → S1 absorption band (up to λmax ≈ 500 nm with julolidine substitution) and (b) decreased thermal stability of the metastable E-isomer, i.e., faster thermal relaxation [30]. However, they also
Emission solvatochromic, solid-state and aggregation-induced emissive α-pyrones and emission-tuneable 1H-pyridines by Michael addition–cyclocondensation sequences
Beilstein J. Org. Chem. 2019, 15, 2684–2703, doi:10.3762/bjoc.15.262
- wavelength maxima appear at around 255 nm. The unsubstituted α-pyrone 6a exhibits its longest wavelength maximum at 381 nm (Table 8, entry 1). A p-methoxyphenyl substituent in the 6-position causes a bathochromic shift (Table 8, entry 2), whereas the same substituent in 4-position leads to a hypsochromic
- , entry 6). The introduction of a more strongly electron-donating substituent, such as N,N-dimethylaminophenyl, causes a significant bathochromic shift (Table 8, entries 3 and 5). Donor–acceptor substitution in positions 4 and 6 causes a further bathochromic shift (Table 8, entry 7). In solution only N,N
- (540 nm) and 6d (489 nm) appear at quite different energies, similar to their corresponding absorption maxima in solution. In comparison to α-pyrone 6a the introduction of two methoxy substituents in derivative 6f results in a bathochromic shift to 526 nm. The solid-state emission of N,N
Arylisoquinoline-derived organoboron dyes with a triaryl skeleton show dual fluorescence
Beilstein J. Org. Chem. 2019, 15, 2612–2622, doi:10.3762/bjoc.15.254
- moiety [37][38], while the donor is related to the electronically variable aryl residue. Comparing the emission maxima of the dyes in the less polar dichloromethane with those in the highly polar dimethyl sulfoxide, additional trends can be seen. Thus, dye 17 shows only a slight bathochromic shift of the
A toolbox of molecular photoswitches to modulate the CXCR3 chemokine receptor with light
Beilstein J. Org. Chem. 2019, 15, 2509–2523, doi:10.3762/bjoc.15.244
- , Supporting Information File 1) and the photoisomerization are observed. When the substituent Y is a halogen atom, we observe a slight bathochromic shift of the π–π* band to higher wavelengths with increasing size of the heteroatom, from 323 nm for Y = H (3e) to 339 nm for Y = I (6e) (Table 3, Figure 4A
- intrinsic activity (α) of the cis-isomers (Figure 4C). This capacity of the Y substituent to alter the electron density is conceivably also related to its capacity to induce a bathochromic shift of the π–π* band of the trans-isomer. Potential evidence for this can be extracted from the significant
- correlation between the bathochromic shift and intrinsic activity of PSS360 (Figure 4D) for the subseries 3e, 4d, 6b and 6d–h, which only differ in the nature of Y group (Figure 4C, Table 4). Conclusion We report a toolbox of 31 photochromic small-molecule CXCR3 receptor ligands based on the modeling-assisted
Photochromic diarylethene ligands featuring 2-(imidazol-2-yl)pyridine coordination site and their iron(II) complexes
Beilstein J. Org. Chem. 2019, 15, 2428–2437, doi:10.3762/bjoc.15.235
- are in the 310–323 nm range. Interestingly, the carbocycle size and the presence/absence of carbonyl group are weakly reflected in the position of absorption maxima of open-ring isomers. For example, the reduction of carbonyl group in 3 (compared to 4) leads to insignificant bathochromic shift of the
- 504 nm in toluene, while a hypsochromic shift of 14 nm was observed in acetonitrile. This influence of solvent polarity was detected for all ligands [39]. The carbonyl group in the ethene bridge of 3 causes a significant bathochromic shift (68 nm in toluene) of the closed-ring isomer maximum in
Click chemistry towards thermally reversible photochromic 4,5-bisthiazolyl-1,2,3-triazoles
Beilstein J. Org. Chem. 2019, 15, 2161–2169, doi:10.3762/bjoc.15.213
- (R = OMe, 570 nm) and 6c (R = CN, 570 nm) in hexane (Scheme 3) [36]. In triazoles, while the introduction of electron-donating methoxy groups had little effect on the absorption maximum wavelengths, the introduction of electron-withdrawing cyano groups induced a large bathochromic shift. This
An overview of the cycloaddition chemistry of fulvenes and emerging applications
Beilstein J. Org. Chem. 2019, 15, 2113–2132, doi:10.3762/bjoc.15.209
- , this can result in a bathochromic shift [2][42]. Consideration of frontier molecular orbital theory allows the electronic nature and general reactivity patterns of fulvenes to be interpreted. Fulvene cycloadditions The multiple cycloaddition pathways observed for fulvenes provides access to a diverse
Fluorinated azobenzenes as supramolecular halogen-bonding building blocks
Beilstein J. Org. Chem. 2019, 15, 2013–2019, doi:10.3762/bjoc.15.197
- significantly strengthened in solution. However, the bathochromic shift of the π→π* band leads to a partial overlap with the n→π* band, making it slightly more difficult to address. The introduction of iodine substituents is furthermore accompanied with a diminishing thermal half-life. A series of three
- , which is very desirable for application in supramolecular systems [12][13][35]. Tetra- and octafluorinated A1 and A2 show clear spectral separation of the n→π* bands, whereas the extended π-system of iodoethynyl A3 lead to a bathochromic shift of the π→π* band by 24 nm, now partially overlapping with
- iodoethynyl group, as trade-off, photophysical properties are changing. The bathochromic shift of the π→π* band leads to an overlap with the n→π* excitation, making it more difficult to address, together with a diminishing thermal half-life. Both effects can be qualitatively reproduced and understood with the
Functional panchromatic BODIPY dyes with near-infrared absorption: design, synthesis, characterization and use in dye-sensitized solar cells
Beilstein J. Org. Chem. 2019, 15, 1758–1768, doi:10.3762/bjoc.15.169
- spacer [14][21][23][24]. Introduction of such units on those positions is known to lead to a larger bathochromic shift of the S0→S1 absorption band than the same substitution on its 2nd and 6th positions [25]. A thiophene-triphenylamine unit was selected among the reported electron-donating units, due to
- Table 1 and Figure 5a). This suggests no self-aggregation of the alkylated dye occurs on the oxide surface, which can be explained by the presence of the co-adsorbent CDCA, and of the multiple alkyl chain substitution of the TPA units. On the other hand, a bathochromic shift of the absorption profile of
Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)2A fluorescent dyes
Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167
- , the three dyes showed a bathochromic shift of the fluorescence band with increasing solvent polarity from toluene to DMF (i.e., positive fluorescence solvatochromism). Thus, the Stokes shift (SS) values of the three dyes increase with increasing solvent polarity. Compared with OUY-2, OUK-2 and OUJ-2
- -2, 592 nm for OUK-2, and 557 nm for OUJ-2, which showed a significant bathochromic shift by 97 nm, 112 nm, and 48 nm, respectively, compared with those in toluene. The solid-state Φf value is below 0.02 for OUY-2 and OUK-2 and 0.09 for OUJ-2, which are much lower than those in toluene. It is well
- electron-withdrawing ability of the azine ring lowers the LUMO energy level of the (D–π–)2A fluorescent dyes. Consequently, the fact revealed that the bathochromic shift of the ICT-based photoabsorption band in the order of OUY-2 < OUK-2 < OUJ-2 is attributed to the stabilization of the LUMO energy level
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