A photoresponsive glycosidase mimic

Samanta, Mousumi; Krishna, Vagolu Siva; Bandyopadhyay, Subhajit

doi:10.1039/c4cc03394a

Cited by 49 publications

(49 citation statements)

References 51 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The peaks at δ 7.83, 7.34 and 7.20 corresponding to the aromatic protons of the azobenzene unit, gradually decreased in the presence of 366 nm UV light, and were accompanied by upfield shifts with the appearance of three new peaks at δ 7.08, 7.02, and 6.60, corresponding to the same set of aromatic protons. This behavior is consistent with the expected behavior for trans to cis conversion of the azobenzene systems …”

Section: Resultssupporting

confidence: 90%

“…The peaks at d 7.83, 7.34 and 7.20 corresponding to the aromatic protons of the azobenzene unit, gradually decreased in the presence of 366 nm UV light, and were accompanied by upfield shifts with the appearance of three new peaks at d 7.08, 7.02, and 6.60, corresponding to the same set of aromatic protons.T his behavior is consistent with the expected behavior for trans to cis conversion of the azobenzene systems. [48,49] It was reported that the eight-memberedd iazocine systems are thermodynamically stable in the cis conformation. [50,51] We have demonstrated thatt he effect of ring strain responsible for the stability of cis form does not extendt ot he 9-membered ring system,a so ur system was found to be more stable in the trans form.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Modulation of Electronic Mobility of a One‐Dimensional Coordination Polymeric Molecular Wire with Light

Saha

Chatterjee

Hossain

et al. 2019

Chemistry An Asian Journal

Self Cite

View full text Add to dashboard Cite

Metal ions often influence the photoswitching efficiency of ap hotochromic system.T his article reports ao nedimensional polymer having cyclic azobenzenes coordinated to silver ions that are bridged by nitrates. The coordination polymer (CP-2)d isplays ap hotoresponsive behavior.T he switching ability in the polymer form was faster compared to the parenta zobenzene ligand withoutt he metal ions. Azobenzenes are reported to be poorlyc onducting. Here, although the azobenzene ligand does not show significant electronic mobility,t he coordination polymer (CP-2)d isplays am odest conductivity.T he conductance in the cis form of the polymer is significantly higher compared to the trans form. Upon exposure to visible light, the cis form undergoes photoisomerization to the trans form with ad rastic drop in the electronic mobility.T he trans form can be reverted to the cis form thermally or by using UV light.Thus,t his system offers ar eversible control of the conductivity using light.

show abstract

Section: Resultssupporting

confidence: 90%

Section: Resultsmentioning

confidence: 99%

Modulation of Electronic Mobility of a One‐Dimensional Coordination Polymeric Molecular Wire with Light

Saha

Chatterjee

Hossain

et al. 2019

Chemistry An Asian Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…However, catalytic selectivity towards H2O2 production has long been an issue surrounding the direct synthesis approach. With many catalysts often requiring the use of halide [11][12] or acid additives [13] to minimize the over hydrogenation or decomposition pathways, which result in the unselective production of H2O, as shown in Figure 1. Bimetallic AuPd catalysts have been shown to be significantly more selective towards H2O2 generation compared to analogous Pd supported catalysts, likely due to a combination of ensemble and electronic effects.…”

Section: Introductionmentioning

confidence: 99%

Direct Synthesis of Hydrogen Peroxide Using Cs-Containing Heteropolyacid-Supported Palladium–Copper Catalysts

et al. 2019

View full text Add to dashboard Cite

The direct synthesis of hydrogen peroxide (H2O2) from molecular hydrogen and oxygen could represent a green and economically attractive alternative to the current indirect anthraquinone process used for the industrial production of hydrogen peroxide. This reaction has been investigated using palladium supported on the Cs-containing heteropolyacid Cs2.5H0.5PW12O40. In addition, the effect of adding copper as a potential activity promoter was investigated. These catalysts were also evaluated for the subsequent degradation of hydrogen peroxide. The catalytic activity of the 0.5 wt.%Pd/Cs2.5H0.5PW12O40 catalyst towards hydrogen peroxide synthesis was greater than that of both the mono-metallic Cu or bi-metallic Pd-Cu analogues with the incorporation of Cu to Pd resulting in a significant decrease in catalytic selectivity for the formation of hydrogen peroxide. Moreover, 0.5 wt.%Pd/Cs2.5H0.5PW12O40 also showed low activity towards the degradation of hydrogen peroxide. Hence the use of the Cs-containing heteropolyacid as a support for Pd gives higher rates of hydrogen peroxide formation when compared with different supported Pd catalysts prepared using supports used in previous studies.

show abstract

“…External control of catalytic systemsb yl ight is ah ighly challenging and still underdeveloped field of moderno rganic chemistry.I nt he quest for responsive catalytic systems, many advantages arise from the use of light as ac lean, non-invasive stimulus,i nw hich judicious choiceo fi rradiation wavelength may allow precise control over catalyst function, activity and selectivity.Anumber of photoresponsive catalysts have been developed over the last decade, exploiting the established switching properties of azobenzenes,d iarylethenesa nd overcrowded alkenes. [1][2][3][4][5] Promising resultsi np hotochemical control of catalyst activity or selectivity have been achieved through different approaches by harnessing cooperative, [6][7][8][9][10][11][12] steric [13][14][15][16][17][18][19][20] and electronic effects [21][22][23][24][25] of the photo-accessible isomers.…”

Section: Introductionmentioning

confidence: 99%

Bifunctional Molecular Photoswitches Based on Overcrowded Alkenes for Dynamic Control of Catalytic Activity in Michael Addition Reactions

Pizzolato

Collins

Leeuwen

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

The emerging field of artificial photoswitchable catalysis has recently shown striking examples of functional light-responsive systems allowing for dynamic control of activity and selectivity in organocatalysis and metal-catalysed transformations. While our group has already disclosed systems featuring first generation molecular motors as the switchable central core, a design based on second generation molecular motors is lacking. Here, the syntheses of two bifunctionalised molecular switches based on a photoresponsive tetrasubstituted alkene core are reported. They feature a thiourea substituent as hydrogen-donor moiety in the upper half and a basic dimethylamine group in the lower half. This combination of functional groups offers the possibility for application of these molecules in photoswitchable catalytic processes. The light-responsive central cores were synthesized by a Barton-Kellogg coupling of the prefunctionalized upper and lower halves. Derivatization using Buchwald-Hartwig amination and subsequent introduction of the thiourea substituent afforded the target compounds. Control of catalytic activity in the Michael addition reaction between (E)-3-bromo-β-nitrostyrene and 2,4-pentanedione is achieved upon irradiation of stable-(E) and stable-(Z) isomers of the bifunctional catalyst 1. Both isomers display a decrease in catalytic activity upon irradiation to the metastable state, providing systems with the potential to be applied as ON/OFF catalytic photoswitches.

show abstract

A photoresponsive glycosidase mimic

Cited by 49 publications

References 51 publications

Modulation of Electronic Mobility of a One‐Dimensional Coordination Polymeric Molecular Wire with Light

Modulation of Electronic Mobility of a One‐Dimensional Coordination Polymeric Molecular Wire with Light

Direct Synthesis of Hydrogen Peroxide Using Cs-Containing Heteropolyacid-Supported Palladium–Copper Catalysts

Bifunctional Molecular Photoswitches Based on Overcrowded Alkenes for Dynamic Control of Catalytic Activity in Michael Addition Reactions

Contact Info

Product

Resources

About