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Search for "energy transfer" in Full Text gives 110 result(s) in Beilstein Journal of Organic Chemistry.
Microphotochemistry: 4,4'-Dimethoxybenzophenone mediated photodecarboxylation reactions involving phthalimides
Beilstein J. Org. Chem. 2011, 7, 1055–1063, doi:10.3762/bjoc.7.121
- an indicator for “over-irradiation”. Mechanistic scenario For ketone-sensitized photodecarboxylations involving phthalimides, energy transfer and electron transfer processes have both been proposed [44][52]. A similar, simplified scenario is depicted in Scheme 8. Due to the comparable triplet
- energies of DMBP (T1 = 69.4 kcal/mol or 290 kJ/mol [53]) and phthalimides (2: T1 = 71 kcal/mol or 297 kJ/mol [39]), energy transfer (Scheme 8, path A) is not very efficient but has been confirmed spectroscopically for a related N-phthalimidocarboxylate/benzophenone pair [52]. Subsequent electron transfer
Fine-tuning alkyne cycloadditions: Insights into photochemistry responsible for the double-strand DNA cleavage via structural perturbations in diaryl alkyne conjugates
Beilstein J. Org. Chem. 2011, 7, 813–823, doi:10.3762/bjoc.7.93
- (Figure 8c). Only glycerol at pH 6 and glycerol and DMSO at pH 8 showed ~10% of protection. Little effect was observed for NaN3, suggesting that the formation of singlet oxygen via triplet energy transfer is inefficient, possibly because of a short triplet lifetime and fast intramolecular photocyclization
Photoinduced electron-transfer chemistry of the bielectrophoric N-phthaloyl derivatives of the amino acids tyrosine, histidine and tryptophan
Beilstein J. Org. Chem. 2011, 7, 518–524, doi:10.3762/bjoc.7.60
- temperature and in ethanol at low temperatures are known: Triplet acetone, acetophenone and xanthone in acetonitrile are quenched by 1 via energy transfer; the rate constant is almost diffusion-controlled and somewhat smaller for benzophenone. The sole product from the photolysis of 1 is the double hydrogen
Supramolecular FRET photocyclodimerization of anthracenecarboxylate with naphthalene-capped γ-cyclodextrin
Beilstein J. Org. Chem. 2011, 7, 290–297, doi:10.3762/bjoc.7.38
- .7.38 Abstract γ-Cyclodextrin (CD) derivatives with a naphthalene moiety anchored to one or two of the glucose units of the CD were synthesized in order to investigate the effects of flexible and rigid capping upon complexation, as well as Förster resonance energy transfer (FRET) and photochirogenic
- Förster resonance energy transfer (FRET) sensitization. Results and Discussion Naphthalene-capped γ-CD 6 was synthesized by the reaction of 6A,6C-ditosyl-γ-CD [23] with disodium 2,6-naphthalenedicarboxylate in DMSO. An attempt to synthesize the regioisomeric 6A,6D-(2,6-naphthalenedicarboxyl)-γ-CD by
- wavelength (296 nm) and the internal filter effect of AC at 350–400 nm is negligible (absorbance <0.1). Considering the nice spectral overlap of the naphthalene fluorescence with the AC absorption (Figure 4), we conclude that Förster resonance energy transfer (FRET) is operating from naphthalene-appended 7
Photocycloaddition of aromatic and aliphatic aldehydes to isoxazoles: Cycloaddition reactivity and stability studies
Beilstein J. Org. Chem. 2011, 7, 127–134, doi:10.3762/bjoc.7.18
- ]. Surprisingly, in the absence of aldehydes as the potential reaction partners, the conversions of 7f–h were significantly lower, suggesting the possibility of an energy transfer from the excited singlet or triplet aldehyde to the isoxazole. Since the photolysis of 7d and 7e in presence of benzaldehyde showed
Photocycloadditions and photorearrangements
Beilstein J. Org. Chem. 2011, 7, 111–112, doi:10.3762/bjoc.7.15
- excited state is generated either by direct light absorption or by energy transfer sensitization. This excited state has to be sufficiently well characterized in order to understand its chemical and physical behaviour. Organic molecules can react either as triplet or singlet excited states, often showing
Gelation or molecular recognition; is the bis-(α,β-dihydroxy ester)s motif an omnigelator?
Beilstein J. Org. Chem. 2010, 6, 1079–1088, doi:10.3762/bjoc.6.123
- collected for about 8 h and transformed into the conventional scattering law, S(Q,ω) (arbitrary units), vs. energy transfer, Et (cm-1), using standard programs. Schröder–van Laar analysis for the melting of toluene (open symbols) and ethanol/water (filled symbols) gels formed from G6 (circles) and G8
Conjugated polymers containing diketopyrrolopyrrole units in the main chain
Beilstein J. Org. Chem. 2010, 6, 830–845, doi:10.3762/bjoc.6.92
- absorption of visible light by the DPP chromophore, and a rapid one arising from additional absorption of UV-light by the phenylene comonomer unit followed by energy transfer to the DPP chromophore. The actual mechanism of photodecomposition remains unclear. Comparative studies indicated that conjugated DPP
A perfluorocyclopentene based diarylethene bearing two terpyridine moieties – synthesis, photochemical properties and influence of transition metal ions
Beilstein J. Org. Chem. 2010, 6, No. 53, doi:10.3762/bjoc.6.53
- processes between the ruthenium nuclei. On the other hand the closed isomer 10aC might act as an acceptor; a similar effect has been observed with a spiropyran moiety bridging two terpyridine units, whose (closed) merocyanine form inhibits the energy transfer between metal centres and thus acts as a T
N-acylation of ethanolamine using lipase: a chemoselective catalyst
Beilstein J. Org. Chem. 2009, 5, No. 10, doi:10.3762/bjoc.5.10
- less reaction time, taking only 4–5 min on solid support and 40–50 min in solution phase while low yields were obtained conventionally even after 4–5 h (Figure 1). In the microwave, the heating is homogenous whereas conventional energy transfer through contact, is comparatively slow and not so
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