Chiral signs of TPPS co-assemblies with chiral gelators: role of molecular and supramolecular chirality

2016 ◽  
Vol 52 (84) ◽  
pp. 12434-12437 ◽  
Author(s):  
Qiuling Wang ◽  
Li Zhang ◽  
Dong Yang ◽  
Tiesheng Li ◽  
Minghua Liu
Keyword(s):  
Chiral Molecules ◽  
Molecular Chirality ◽  
Supramolecular Chirality ◽  
J Aggregates

The chirality of TPPS J aggregates followed the supramolecular chirality of assemblies from chiral molecules rather than the molecular chirality.

scholarly journals Chiral Magneto-Electrochemistry

2018 ◽  
Vol 4 (3) ◽  
pp. 36 ◽  
Author(s):  
Anup Kumar ◽  
Prakash Mondal ◽  
Claudio Fontanesi
Keyword(s):  
Magnetic Field ◽  
Experimental Studies ◽  
Spin Accumulation ◽  
Chiral Molecules ◽  
Electrochemical System ◽  
Ferromagnetic Electrodes ◽  
Spin Polarized ◽  
The Magnetic Field ◽  
Research Domain

Magneto-electrochemistry (MEC) is a unique paradigm in science, where electrochemical experiments are carried out as a function of an applied magnetic field, creating a new horizon of potential scientific interest and technological applications. Over time, detailed understanding of this research domain was developed to identify and rationalize the possible effects exerted by a magnetic field on the various microscopic processes occurring in an electrochemical system. Notably, until a few years ago, the role of spin was not taken into account in the field of magneto-electrochemistry. Remarkably, recent experimental studies reveal that electron transmission through chiral molecules is spin selective and this effect has been referred to as the chiral-induced spin selectivity (CISS) effect. Spin-dependent electrochemistry originates from the implementation of the CISS effect in electrochemistry, where the magnetic field is used to obtain spin-polarized currents (using ferromagnetic electrodes) or, conversely, a magnetic field is obtained as the result of spin accumulation.

scholarly journals A hidden catalysis: metal-, and organocatalyst-free one-pot assembly of chiral aza-tricyclic molecules containing six contiguous stereocenters

2020 ◽  
Author(s):  
Dung Do
Keyword(s):  
Chemical Space ◽  
Structural Diversity ◽  
Therapeutic Agents ◽  
Chiral Molecules ◽  
One Pot ◽  
Complex Molecules ◽  
Chiral Complex ◽  
Enamine Catalysis ◽  
Daunting Challenge

<p></p><p>Chiral molecules with their defined 3-D structures are of paramount importance for the study of chemical biology and drug discovery. Having rich structural diversity and unique stereoisomerism, chiral molecules offer a large chemical space that can be explored for the design of new therapeutic agents.<sup>1</sup> In practice, chiral architectures are usually prepared from organometallic and organocatalytic processes where a transition metal or an organocatalyst is tailor-made for a desired reaction. As a result, developing a method that enables rapid assembly of chiral complex molecules under a metal- and organocatalyst-free condition represents a daunting challenge. Here we developed a straightforward one-pot procedure to create a chiral 3-D structure from 2-D structures and an amino acid without any chiral catalyst. The center of this research is the design of a <a>special chiral spiroimidazolidinone cyclohexadienone intermediate</a>, a merger of a chiral reactive substrate with multiple nucleophillic/electrophillic sites and a transient organocatalyst. <a>This unique substrate-catalyst (“sub-catalyst”) dual role of the intermediate was displayed in its aza-Michael/Michael cascade reaction with an </a>α,β-unsaturated aldehyde under an iminium/enamine catalysis. <a>The enhanced co-ordinational proximity of the chiral substrate and catalyst</a> in the transition state resulted in a substantial steric discrimination and an excellent overall diastereoselectivity. Aza-tricylic molecules with six contiguous stereocenters were assembled from <i>N</i>-alkylated aminophenols, α,β-unsaturated aldehydes and chiral α-amino acids under a hidden “sub-catalysis” where the strategically produced “sub-catalyst” does not present in initial components of the reaction. The success of this methodology will pave the way for many efficient preparations of chiral complex molecules.</p><br><p></p>

Diverse Role of Solvents in Controlling Supramolecular Chirality

2019 ◽  
Vol 25 (31) ◽  
pp. 7426-7437 ◽  
Author(s):  
Shixin Xue ◽  
Pengyao Xing ◽  
Jingbo Zhang ◽  
Yongfei Zeng ◽  
Yanli Zhao
Keyword(s):  
Supramolecular Chirality

Exploring the role of molecular chirality in the photo-responsiveness of dipeptide-based gels

2017 ◽  
Vol 5 (17) ◽  
pp. 3163-3171 ◽  
Author(s):  
Zhonghui Chen ◽  
Ziyu Lv ◽  
Guangyan Qing ◽  
Taolei Sun
Keyword(s):  
Uv Light ◽  
Light Irradiation ◽  
Molecular Chirality ◽  
Uv Light Irradiation

Chiral effect: upon UV light irradiation, the l-gel has a markedly faster gel–sol transition than the d-gel.

Autoamplification of Molecular Chirality through the Induction of Supramolecular Chirality

2014 ◽  
Vol 126 (20) ◽  
pp. 5173-5177 ◽  
Author(s):  
Derk Jan van Dijken ◽  
John M. Beierle ◽  
Marc C. A. Stuart ◽  
Wiktor Szymański ◽  
Wesley R. Browne ◽  
...  
Keyword(s):  
Molecular Chirality ◽  
Supramolecular Chirality

Role of the hydrogen-bond in porphyrin J-aggregates

RSC Advances ◽  
2012 ◽  
Vol 2 (33) ◽  
pp. 12989 ◽  
Author(s):  
Valentina Villari ◽  
Placido Mineo ◽  
Emilio Scamporrino ◽  
Norberto Micali
Keyword(s):  
Hydrogen Bond ◽  
J Aggregates

scholarly journals A hidden catalysis: metal-, and organocatalyst-free one-pot assembly of chiral aza-tricyclic molecules containing six contiguous stereocenters

2020 ◽  
Author(s):  
Dung Do
Keyword(s):  
Chemical Space ◽  
Structural Diversity ◽  
Therapeutic Agents ◽  
Chiral Molecules ◽  
One Pot ◽  
Complex Molecules ◽  
Chiral Complex ◽  
Enamine Catalysis ◽  
Daunting Challenge

<p></p><p>Chiral molecules with their defined 3-D structures are of paramount importance for the study of chemical biology and drug discovery. Having rich structural diversity and unique stereoisomerism, chiral molecules offer a large chemical space that can be explored for the design of new therapeutic agents.<sup>1</sup> In practice, chiral architectures are usually prepared from organometallic and organocatalytic processes where a transition metal or an organocatalyst is tailor-made for a desired reaction. As a result, developing a method that enables rapid assembly of chiral complex molecules under a metal- and organocatalyst-free condition represents a daunting challenge. Here we developed a straightforward one-pot procedure to create a chiral 3-D structure from 2-D structures and an amino acid without any chiral catalyst. The center of this research is the design of a <a>special chiral spiroimidazolidinone cyclohexadienone intermediate</a>, a merger of a chiral reactive substrate with multiple nucleophillic/electrophillic sites and a transient organocatalyst. <a>This unique substrate-catalyst (“sub-catalyst”) dual role of the intermediate was displayed in its aza-Michael/Michael cascade reaction with an </a>α,β-unsaturated aldehyde under an iminium/enamine catalysis. <a>The enhanced co-ordinational proximity of the chiral substrate and catalyst</a> in the transition state resulted in a substantial steric discrimination and an excellent overall diastereoselectivity. Aza-tricylic molecules with six contiguous stereocenters were assembled from <i>N</i>-alkylated aminophenols, α,β-unsaturated aldehydes and chiral α-amino acids under a hidden “sub-catalysis” where the strategically produced “sub-catalyst” does not present in initial components of the reaction. The success of this methodology will pave the way for many efficient preparations of chiral complex molecules.</p><br><p></p>

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