Isolable Chiral Aggregates of Achiral π-Conjugated Carboxylic Acids.

Summary of "Isolable Chiral Aggregates of Achiral π-Conjugated Carboxylic Acids."

The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is understood in terms of designing these chiral aggregates. Herein, we report a strategy for creating such isolable chiral aggregates from achiral building blocks that retain chiral memory after the facile physical removal of the chiral templates. This strategy was used for the isolation of chiral homoaggregates of neutral achiral π-conjugated carboxylic acids in pure aqueous solution. Under what we have termed an "interaction-substitution" mechanism, we generated chiral homoaggregates of a variety of π-conjugated carboxylic acids by using carboxymethyl cellulose (CMC) as a mediator in acidic aqueous solutions. These aggregates were subsequently isolated from the CMC templates whilst retaining their memorized supramolecular chirality. Circular dichroism (CD) spectra of the aggregates formed in the acidic CMC solution exhibited bisignated exciton-coupled signals of various signs and intensities that were maintained in the isolated pure homoaggregates of the achiral π-conjugated carboxylic acids. The memory of the supramolecular chirality in the isolated aggregates was ascribed to the substitution of COOH/COOH hydrogen-bonding interaction between the carboxylic acid groups within the aggregates for the hydrogen-bonding interactions between the COOH groups of the building blocks and the chiral templates. We expect that this "interaction-substitution" procedure will open up a new route to isolable pure chiral aggregates from achiral species.


Department of Chemistry, College of Chemistry and Chemical Engineering and the MOE Key Laboratory of Analytical Sciences, Xiamen University, Xiamen 361005 (P. R. China), Fax: (+86) 592-218-6401.

Journal Details

This article was published in the following journal.

Name: Chemistry (Weinheim an der Bergstrasse, Germany)
ISSN: 1521-3765
Pages: 3631-6


DeepDyve research library

PubMed Articles [4854 Associated PubMed Articles listed on BioPortfolio]

KetoABNO/NOx Cocatalytic Aerobic Oxidation of Aldehydes to Carboxylic Acids and Access to α-Chiral Carboxylic Acids via Sequential Asymmetric Hydroformylation/Oxidation.

A method for aerobic oxidation of aldehydes to carboxylic acids has been developed using organic nitroxyl and NOx cocatalysts. KetoABNO (9-azabicyclo[3.3.1]nonan-3-one N-oxyl) and NaNO2 were identifie...

Synthesis and characterization of mixed ligand chiral nanoclusters.

Chiral mixed ligand silver nanoclusters were synthesized in the presence of a chiral and an achiral ligand. While the chiral ligand led mostly to the formation of nanoparticles, the presence of the ac...

Lithium Enolates in the Enantioselective Construction of Tetrasubstituted Carbon Centers with Chiral Lithium Amides as Noncovalent Stereodirecting Auxiliaries.

Lithium enolates derived from carboxylic acids are ubiquitous intermediates in organic synthesis. Asymmetric transformations with these intermediates, a central goal of organic synthesis, are typicall...

Chiral Sensor for Enantiodiscrimination of Varied Acids.

A chiral thiophosphoroamide 4 derived from (1R,2R)-1,2-diaminocyclohexane is used as a highly effective chiral sensor for the chiral recognition of varied acids via ion-pairing and hydrogen-bonding in...

"Inherently Chiral" Ionic-Liquid Media: Effective Chiral Electroanalysis on Achiral Electrodes.

To achieve enantioselective electroanalysis either chiral electrodes or chiral media are needed. High enantiodiscrimination properties can be granted by the "inherent chirality" strategy of developing...

Clinical Trials [620 Associated Clinical Trials listed on BioPortfolio]

A Study to Investigate Effects of Omega-3 Carboxylic Acids and Dapagliflozin on Liver Fat Content in Diabetic Patients

This study is a double-blind randomized, placebo-controlled, parallel-group, 12 week study performed in up to 5 centres in Sweden to assess the effect of Omega-3 carboxylic acids and dapag...

Platelet Leukocyte Aggregates in Acute Cardiac Syndrome vs Healthy Volunteers

This project aims to refine previous studies including the investigators work recently published in August 2012 Journal Thrombosis and Thrombolysis. That study showed a relationship betwee...

A Study to Investigate How Common Pancreatic Exocrine Insufficiency (PEI) is in Patients With Type 2 Diabetes and Also to Investigate the Uptake of a Single Dose of EPANOVA® or OMACOR® in Patients With Different Degrees of PEI

This study is a 2-part open-label, randomized, crossover, multicenter, non-therapeutic Phase II study to investigate the presence of pancreatic exocrine insufficiency (PEI) in patients wit...

The Health Benefits of Conjugated Linoleic Acid (CLA) for Asthma & Allergy

Conjugated linoleic acids (CLA) are naturally occurring free fatty acids derived from the tissues and milk of ruminant animals such as cows. CLA has multiple biological properties includin...

Dietary Fatty Acids as Complementary Therapy in Type 2 Diabetes Mellitus

The purpose of the study is to see how a dietary oil called conjugated linoleic acid, or CLA, might be useful in combination with diabetes medication. Some studies show that CLA can modes...

Medical and Biotech [MESH] Definitions

Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.

Enzymes which catalyze the hydrolysis of carboxylic acid esters with the formation of an alcohol and a carboxylic acid anion.

Compounds consisting of chains of AMINO ACIDS alternating with CARBOXYLIC ACIDS via ester and amide linkages. They are commonly cyclized.

Steroid acids and salts. The primary bile acids are derived from cholesterol in the liver and usually conjugated with glycine or taurine. The secondary bile acids are further modified by bacteria in the intestine. They play an important role in the digestion and absorption of fat. They have also been used pharmacologically, especially in the treatment of gallstones.

Carboxylic acids that have open-chain molecular structures as opposed to ring-shaped structures.

Quick Search

DeepDyve research library

Searches Linking to this Article