Photochromic dithienylethenes characterized by <i>in situ</i> irradiation NMR-spectroscopy and electrochemically induced responsiveness on gold substrates

Irmer, Jonas von; Frieß, Florian; Herold, Dominik; Kind, Jonas; Thiele, Christina M.; Gallei, Markus

doi:10.1039/c9tc04495g

Cited by 4 publications

(4 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This photochromic system exhibits a reversible photo‐cyclization reaction of the open form 1 o upon UV illumination to a ring closed isomer 1 c (365 nm, PSS 70 % of 1 c ), which is thermally stable in the dark with no signs of fatigue or undesirable secondary reactions (Scheme 1). [21] …”

Section: Resultsmentioning

confidence: 99%

“…This photochromic system exhibits a reversible photo-cyclization reaction of the open form 1 o upon UV illumination to a ring closed isomer 1 c (365 nm, PSS 70 % of 1 c), which is thermally stable in the dark with no signs of fatigue or undesirable secondary reactions (Scheme 1). [21] Upon illumination in the visible wavelength range (e. g. 525 nm) the ring-opened isomer 1 o is obtained by inducing cycloreversion of the closed form 1 c.…”

Section: Simultaneous Nmr and Uv/vis Measurementsmentioning

confidence: 99%

“…In this work we present the development of the micro‐Helmholtz setup for combined UV/Vis and NMR spectroscopy, compare it with the improved dip‐probe setup and demonstrate the versatility of the two setups. As proof‐of‐principle both setups are applied to a well‐studied photochromic dithienylethene system 1 [21] . The obtained UV/Vis and NMR spectra are compared to NMR and UV/Vis spectra acquired in a conventional manner.…”

Section: Introductionmentioning

confidence: 99%

“…As proof-of-principle both setups are applied to a well-studied photochromic dithienylethene system 1. [21] The obtained UV/Vis and NMR spectra are compared to NMR and UV/Vis spectra acquired in a conventional manner.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Evolution of a Combined UV/Vis and NMR Setup with Fixed Pathlengths for Mass‐limited Samples

Herold,

Brauser,

Kind

et al. 2024

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

The investigation of reaction mechanisms is a complex task that usually requires the use of several techniques. To obtain as much information as possible on the reaction and any intermediates ‐ possibly invisible to one technique ‐ the combination of techniques is a solution. In this work we present a new setup for combined UV/Vis and NMR spectroscopy and compare it to an established alternative. The presented approach allows a versatile usage of different commercially‐available components like mirrors and fiber bundles as well as different fixed pathlengths according to double transmission or single transmission measurements. While a previous approach is based on a dip‐probe setup for conventional NMR probes, the new one is based on a micro‐Helmholtz coil array (LiquidVoxel™). This makes the use of rectangular cuvettes possible, which ensure well‐defined pathlengths allowing for quantification of species. Additionally, very low quantities of compound can be analyzed due to the microfabrication and small cuvette size used. As proof‐of‐principle this new setup for combined UV/Vis and NMR spectroscopy is used to examine a well‐studied photochromic system of the dithienylethene compound class. A thorough comparison of the pros and cons of the two setups for combined UV/Vis and NMR measurements is performed.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Simultaneous Nmr and Uv/vis Measurementsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Evolution of a Combined UV/Vis and NMR Setup with Fixed Pathlengths for Mass‐limited Samples

Herold,

Brauser,

Kind

et al. 2024

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

show abstract

LED‐NMR Monitoring of an Enantioselective Catalytic [2+2] Photocycloaddition

2020

View full text Add to dashboard Cite

We report that an NMR spectrometer equipped with a high‐power LED light source can be used to study a fast enantioselective photocatalytic [2+2] cycloaddition. While traditional ex situ applications of NMR provide considerable information on reaction mechanisms, they are often ineffective for observing fast reactions. Recently, motivated by renewed interest in organic photochemistry, several approaches have been reported for in situ monitoring of photochemical reactions. These previously disclosed methods, however, have rarely been applied to rapid (<5 min) photochemical reactions. Furthermore, these approaches have not previously been used to interrogate the mechanisms of photocatalytic energy‐transfer reactions. In the present work, we describe our experimental setup and demonstrate its utility by determining a phenomenological rate law for a model photocatalytic energy‐transfer cycloaddition reaction.

show abstract

Extraction of pure component spectra from ex situ illumination UV/Vis and NMR spectroscopy

Herold,

Kind,

Frieß

et al. 2023

Photochem Photobiol Sci

View full text Add to dashboard Cite

Obtaining understanding of a photochemical reaction relies on the observation, identification and quantification of the compounds involved. The photochemical properties of the individual components are of particular importance, and their determination, however, is not always trivial. This is also true for the quantitative measure on the ability to absorb light, the extinction coefficient εi if more than one species i is present and two or more species absorb light of the same wavelength. In this work, it is demonstrated how pure component spectra can be obtained with a simple combination of successive and repeated ex situ illumination, UV/Vis and NMR spectroscopy. From the complementary information accessible, the wavelength-dependent extinction coefficients of all species can be calculated yielding the pure component spectra. A comparison with published data shows excellent agreement and thus proves that this approach is highly reliable. Graphical abstract

show abstract

Photochromic dithienylethenes characterized by in situ irradiation NMR-spectroscopy and electrochemically induced responsiveness on gold substrates

Abstract: The photochromic and electrochemical switching capabilities of two dithienylethenes with different substitutions and their self-assembled monolayers on gold surfaces are characterized by in situ NMR-spectroscopy and cyclic voltammetry.

Cited by 4 publications

References 41 publications

Evolution of a Combined UV/Vis and NMR Setup with Fixed Pathlengths for Mass‐limited Samples

Evolution of a Combined UV/Vis and NMR Setup with Fixed Pathlengths for Mass‐limited Samples

LED‐NMR Monitoring of an Enantioselective Catalytic [2+2] Photocycloaddition

Extraction of pure component spectra from ex situ illumination UV/Vis and NMR spectroscopy

Contact Info

Product

Resources

About