Assessment of the Organocatalytic Activity of Chiral L-Proline-Based Deep Eutectic Solvents Based on their Structural Features

10.26434/chemrxiv.12403145.v1 ◽

2020 ◽

Author(s):

Matteo Tiecco ◽

Diego Alonso ◽

Diego Ros Ñíguez ◽

Gianluca Ciancaleoni ◽

Gabriela Guillena ◽

...

Keyword(s):

Michael Addition ◽

Deep Eutectic Solvents ◽

Structural Features ◽

Dft Studies ◽

Nmr Studies ◽

Asymmetric Michael Addition ◽

Solvent Component ◽

Reaction Media

<div><div><div><p>In this paper L-Proline-based Chiral Deep Eutectic Solvents (CDESs) were prepared and used as green and organocatalytic reaction media in a probe asymmetric Michael addition; in this reaction the L-Proline acts as solvent component as well as chiral organocatalyst. The results were analysed with NMR studies taking in account the availability of the L-Proline considering the strength of the association of it with the counterpart of the liquids. With DFT studies, the geometry and energy of the adducts are showed and a qualitative rationale to the reaction stereoisomers distribution is given.</p></div></div></div>

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Probing the Structural Features and the Micro-heterogeneity of Various Deep Eutectic Solvents and their Water Dilutions by the Photophysical Behaviour of Two Fluorophores

10.26434/chemrxiv.13395683.v1 ◽

2020 ◽

Author(s):

Matteo Tiecco ◽

Irene Di Guida ◽

Pier Luigi Gentili ◽

Raimondo Germani ◽

Carmela Bonaccorso ◽

...

Keyword(s):

Hydrogen Bond ◽

Transient Absorption ◽

Photophysical Properties ◽

Deep Eutectic Solvents ◽

Structural Features ◽

Solvation Dynamics ◽

Structured Systems ◽

Reduced Viscosity ◽

Bond Network ◽

Fluorescent Molecules

<div><div><div><p>The structural features of a series of diverse Deep Eutectic Solvents (DESs) have been investigated and characterized by means of two fluorescent probes. The spectral and photophysical properties of the latter are strictly dependent on the experienced environment, so that they can provide insights into the polarity, viscosity, hydrogen-bond network, and micro-heterogeneity of the various DESs.</p><p>In fact, the investigated DESs exhibit a variety of properties with regards to their hydrophilicity, acidity, and hydrogen-bond ability, and these details were deeply probed by the two fluorescent molecules. The effect of the addition of water, which is a key strategy for tuning the properties of these structured systems, was also tested. In particular, the excited state dynamics of the probes, measured by femtosecond-resolved transient absorption, proved instrumental in understanding the changes in the structural properties of the DESs, namely reduced viscosity and enhanced heterogeneity, as the water percentage increases. Differences between the various DESs in terms of both local microheterogeneity and bulk viscosity also emerged from the peculiar multi-exponential solvation dynamics undergone by the excited states of the probes.</p></div></div></div>

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Probing the Structural Features and the Micro-heterogeneity of Various Deep Eutectic Solvents and their Water Dilutions by the Photophysical Behaviour of Two Fluorophores

10.26434/chemrxiv.13395683 ◽

2020 ◽

Author(s):

Matteo Tiecco ◽

Irene Di Guida ◽

Pier Luigi Gentili ◽

Raimondo Germani ◽

Carmela Bonaccorso ◽

...

Keyword(s):

Hydrogen Bond ◽

Transient Absorption ◽

Photophysical Properties ◽

Deep Eutectic Solvents ◽

Structural Features ◽

Solvation Dynamics ◽

Structured Systems ◽

Reduced Viscosity ◽

Bond Network ◽

Fluorescent Molecules

<div><div><div><p>The structural features of a series of diverse Deep Eutectic Solvents (DESs) have been investigated and characterized by means of two fluorescent probes. The spectral and photophysical properties of the latter are strictly dependent on the experienced environment, so that they can provide insights into the polarity, viscosity, hydrogen-bond network, and micro-heterogeneity of the various DESs.</p><p>In fact, the investigated DESs exhibit a variety of properties with regards to their hydrophilicity, acidity, and hydrogen-bond ability, and these details were deeply probed by the two fluorescent molecules. The effect of the addition of water, which is a key strategy for tuning the properties of these structured systems, was also tested. In particular, the excited state dynamics of the probes, measured by femtosecond-resolved transient absorption, proved instrumental in understanding the changes in the structural properties of the DESs, namely reduced viscosity and enhanced heterogeneity, as the water percentage increases. Differences between the various DESs in terms of both local microheterogeneity and bulk viscosity also emerged from the peculiar multi-exponential solvation dynamics undergone by the excited states of the probes.</p></div></div></div>

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Pyrrolidinyl-Camphor Derivatives as a New Class of Organocatalyst for Direct Asymmetric Michael Addition of Aldehydes and Ketones to β-Nitroalkenes

Chemistry - A European Journal ◽

10.1002/chem.201000483 ◽

2010 ◽

Vol 16 (23) ◽

pp. 7030-7038 ◽

Cited By ~ 69

Author(s):

Ying-Fang Ting ◽

Chihliang Chang ◽

Raju Jannapu Reddy ◽

Dhananjay R. Magar ◽

Kwunmin Chen

Keyword(s):

Michael Addition ◽

New Class ◽

Asymmetric Michael Addition ◽

Aldehydes And Ketones ◽

Camphor Derivatives

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Base‐Free Copper‐Catalyzed Azide‐Alkyne Click Cycloadditions (CuAAc) in Natural Deep Eutectic Solvents as Green and Catalytic Reaction Media

European Journal of Organic Chemistry ◽

10.1002/ejoc.202101044 ◽

2021 ◽

Author(s):

Salvatore Vincenzo Giofrè ◽

Matteo Tiecco ◽

Angelo Ferlazzo ◽

Roberto Romeo ◽

Gianluca Ciancaleoni ◽

...

Keyword(s):

Catalytic Reaction ◽

Deep Eutectic Solvents ◽

Natural Deep Eutectic Solvents ◽

Reaction Media

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ChemInform Abstract: Asymmetric Michael Addition of Ketones to Nitroolefins: Pyrrolidinyl-oxazole-carboxamides as New Efficient Organocatalysts.

ChemInform ◽

10.1002/chin.201512034 ◽

2015 ◽

Vol 46 (12) ◽

pp. no-no

Author(s):

Ahmed Kamal ◽

Manda Sathish ◽

Vunnam Srinivasulu ◽

Jadala Chetna ◽

Kunta Chandra Shekar ◽

...

Keyword(s):

Michael Addition ◽

Asymmetric Michael Addition

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Synthesis of new pyrrolidine-based organocatalysts and study of their use in the asymmetric Michael addition of aldehydes to nitroolefins

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.59 ◽

2017 ◽

Vol 13 ◽

pp. 612-619 ◽

Cited By ~ 1

Author(s):

Alejandro Castán ◽

Ramón Badorrey ◽

José A Gálvez ◽

María D Díaz-de-Villegas

Keyword(s):

Michael Addition ◽

Bulky Substituent ◽

Asymmetric Michael Addition ◽

Iodination Reaction ◽

Chiral Imines ◽

New Compounds ◽

The Michael Addition

New pyrrolidine-based organocatalysts with a bulky substituent at C2 were synthesized from chiral imines derived from (R)-glyceraldehyde acetonide by diastereoselective allylation followed by a sequential hydrozirconation/iodination reaction. The new compounds were found to be effective organocatalysts for the Michael addition of aldehydes to nitroolefins and enantioselectivities up to 85% ee were achieved.

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