Amino Acid-Based Molecular and Membranous Chiral Tools for Enantiomeric Recognition.

Given the need, both academic and industrial, for new approaches and technologies for chiral discrimination of enantiomers, the present work demonstrates the development through rational design and integration of two new chiral platforms (molecular and membranous) for enantioselective recognition through visual as well as microscopic observation. The molecular platform () is based on the tryptophan derivative developed through the condensation of two tryptophan units with terepthaloyl chloride. While based on l-tryptophan recognizes -mandelic acid over the -isomer, the host with reverse chirality () recognizes S-mandelic acid over -isomer.

Enamine/Iminium-based Dual Organocatalytic Systems for Asymmetric Catalysis and Synthesis.

The rational combination of two catalysts to expedite the construction of chiral complex biologically and pharmacologically relevant chiral compounds has widely gained momentum over the past decade. In particular, enamine or iminium catalysis ensuing from the activation of aldehyde or ketone by chiral amine catalysts in conjugation with other organocatalytic cycles has facilitated several asymmetric transformations to yield the enantioenriched products. Regardless of the considerable discussion on the various dual catalytic approaches, literature lacks a comprehensive review focusing on the enamine and iminium-based dual organocatalytic systems.

Amino decorated adenine based metal-organic framework for multi-faceted applications.

Multifunctional metal-organic frameworks with luminescence properties are promising materials for the detection and treatment of toxic pollutants in aqueous media. Herein, an adenine-based multifunctional Zn-MOF {[Zn(AIPA)(Ade)(HO)] using linkers adenine (Ade) and 5-aminoisophthalic acid (AIPA)} was prepared that could selectively detect particular classes of explosives and antibiotics, namely, nitrophenols, tetracyclines and nitrofurans. Moreover, the as-synthesized Zn-MOF displayed a remarkable efficiency for the treatment of antibiotics in water through adsorption and photocatalytic degradation.

Cu(II)-Based Coordination Polymer as a Pristine Form Usable Electrocatalyst for Oxygen Reduction Reaction: Experimental Evaluation and Theoretical Insights into Biomimetic Mechanistic Aspects.

As the postsynthesis-processed metal-organic material-based catalysts for energy applications add additional cost to the whole process, the importance of developing synthesized usable pristine catalysts is quite evident. The present work reports a new Cu-based coordination polymer (Cu-CP) catalyst to be used in its pristine form for oxygen reduction reaction (ORR) application. The catalyst was characterized using single-crystal X-ray diffraction, field emission scanning electron microscopy, and X-ray photoemission spectroscopy.

Chiral gelators for visual enantiomeric recognition.

Introduction of chirality in supramolecular gels has allowed the effective translation and amplification of molecular chirality. Upon integrating the stimuli-responsive nature of these gels with supramolecular chirality, a new platform for the discrimination of the enantiomeric guests through naked eye can be developed. Over the past decade, several groups have reported the development of chiral supramolecular gels for enantioselective recognition through gel formation or collapse.

Through structural isomerism: positional effect of alkyne functionality on molecular optical properties.

Literature studies on the effects of alkyne functionality in manipulating the optical properties of donor-π-acceptor-type molecular scaffolds have been scarce compared to those on the alkene functional group. Here, two structurally isomeric donor-acceptor (D-A) dyes were synthesized to study the positional effect of alkyne functionality (triple bond) on their optical, electrochemical and charge generation properties in order to design efficient dyes for possible application in dye sensitized solar cells (DSSCs). These dyes, named CAPC and PACC, contain carbazole and cyanoacrylic acid as the donor and acceptor units, respectively, and the π-conjugation length within the molecules was controlled by the introduction of an alkyne group.

Molecular-level insights into the self-assembly driven enantioselective recognition process.

The importance of the orientation of functional groups in a chiral environment on enantioselective recognition has been demonstrated. Orientation controlled interactions of functional groups in (R)/(S)-MA lead to a visually differentiable morphology with an arginine-based gelator. The crucial role of various molecular-level interactions discriminating the enantioselective self-assembly has been established using different analytical techniques, crystal structure analysis, and DFT calculations.

Preferential intermolecular interactions lead to chiral recognition: enantioselective gel formation and collapse.

Interesting self-assembly of an amino acid based molecular material into a hydrogel in the presence of selective enantiomeric chiral amines leading to chiral recognition has been demonstrated. Moreover, collapse of a metallogel formed from the same material in the presence of selective enantiomers validated its enantioselective affinity. Importantly, in addition to relevant experimental techniques, DFT studies have been successfully explored to establish chiral recognition through enantioselective gelation.

A long-range emissive mega-Stokes inorganic-organic hybrid material with peripheral carboxyl functionality for As(v) recognition and its application in bioimaging.

We demonstrate a strategy for the recognition of As in aqueous solution using a red-emissive probe based on a perylene-Cu ensemble decorated with peripheral free carboxyl functionality. Single crystal analysis helped us to understand the chemical structure of the probe. To the best of our knowledge, this is the first probe for arsenic detection which emits in the red region (λ = 600 nm).

Plant leaves as natural green scaffolds for palladium catalyzed Suzuki-Miyaura coupling reactions.

This work presents a novel approach of using natural plant leaf surfaces having intricate hierarchical structures as scaffolds for Pd nanoparticles and demonstrated it as a Green dip catalyst for Suzuki-Miyaura coupling reactions in water. The influence of the topographical texture of the plant leaves on the deposition and catalytic properties of Pd nanoparticles are presented and discussed. The catalytic activity can be correlated to the surface texture of the leaves, wherein it has been found that the micro/nanostructures present on the surface strongly influence the assembly and entrapment of the nanoparticles, and thereby control aggregation and leaching of the catalysts.