Chemical Science Blog

A highly efficient scandium-catalysed asymmetric epoxidation reaction with hydrogen peroxide as the oxidant has been developed by researchers in China. The Sc(OTf)₃ complex enabled epoxidation of a wide range of alpha,beta-unsaturated ketones and amides in overall excellent yields and enantioselectivites.

The reaction is also compatible with dilute aqueous hydrogen peroxide, increasing the safety and practicality of current reactions.

Link to journal article
Asymmetric Catalytic Epoxidation of alfa, beta-Unsaturated Carbonyl Compounds with Hydrogen Peroxide: Additive-Free and Wide Substrate Scope
Y Chu et al
Chem. Sci., 2012, DOI: 10.1039/c2sc20218b

Cyanine dyes have been widely used for fluorescent sensory applications in both industry and academia. However, they are limited by drawbacks such as a small Stokes shift (up to 20nm) and concentration quenching effect.

Scientists in China have now designed a red emissive hemicyanine dye that overcomes these drawbacks. The dye possesses a large Stokes shift (>185nm) and shows different colours and intensities over a broad pH range (pH 5-14).

The acid/base-switched red/blue emission transition is reversible and can last for many cycles.

Link to journal article
An AIE-active hemicyanine fluorogen with stimuli-responsive red/blue emission: Extending the pH sensing range by “switch + knob” effect
S Chen et al
Chem. Sci., 2012, DOI: 10.1039/c2sc01108e

Scientists in the US have developed a way to detect and differentiate between mixtures of plasticisers within plastic explosives such as Semtex and C4 to provide information for anti-terrorism activities.

The team bound a fluorescent indicator to a plasma protein, which then binds to the plasticisers. A cross-reactive array was used to reveal which plasticisers were present in the explosive mixtures.

Link to journal article
Exploration of Plasticizer and Plastic Explosive Detection and Differentiation with Serum Albumin Cross-Reactive Arrays
M A Ivy et al
Chem. Sci., 2012, DOI: 10.1039/c2sc20083j

Scientists in China have shown that their N-rich zeolite-like metal-organic framework shows high CO₂ uptake, selective gas adsorption and efficient drug delivery.

Find out more:
N-rich zeolite-like metal-organic framework with sodalite topology: high CO₂ uptake, selective gas adsorption and efficient drug delivery
J-S Qin et al, Chem. Sci., 2012, DOI: 10.1039/c2sc00017b

Scientists in Japan have demonstrated that the supramolecular organisation of ionic liquids is a promising way for constructing highly ion conductive materials. The team used the ionic liquids to make three-dimensional nanochannels that function as efficient transportation pathways for ions.

Link to journal article
Co-organisation of ionic liquids with amphiphilic diethanolamines: construction of 3D continuous ionic nanochannels through the induction of liquid-crystalline bicontinuous cubic phases
T Ichikawa et al
Chem. Sci., 2012, DOI: 10.1039/c2sc00981a

Scientists in Singapore and China say it is due to a hidden force – a coulomb repulsion between the unevenly-bound bonding and non-bonding electron pairs in the hydrogen bond. Understanding the behaviour of water is key to many fields of science and engineering.

Link to journal article
The hidden force opposing ice compression
C Q Sun, X Zhang and W Zheng
Chem. Sci., 2012, DOI: 10.1039/c2sc20066j

A polymer functionalised with boronic acid promises a cheap and quick way to purify antibodies for disease studies, according to scientists in China.

Antibodies, also known as immunoglobulins, are used to investigate disease diagnostics and treatments. They are Y-shaped proteins used by the immune system to identify and neutralise foreign objects such as bacteria and viruses. Capturing and purifying antibodies is essential for these investigations.

The current gold standard for capturing the antibody immunoglobulin G (IgG) uses protein A – a bacterial protein that targets a region at the bottom of the Y part of the IgG molecule – in chromatography. However, disadvantages associated with this method, such as poor protein stability and harsh conditions for releasing the antibody afterwards, inspired Zhen Liu and his team at Nanjing University to look for alternatives.

The antibodies were bound to ligands that were embedded in the mesopores of a polymer

Read the full story in Chemistry World

Link to journal article
Restricted access boronate affinity porous monolith as a protein A mimetic for the specific capture of immunoglobulin G
Yunchun Liu ,  Yue Lu and Zhen Liu
Chem. Sci., 2012, Advance Article, DOI: 10.1039/C2SC20125A

Star-shaped bimetallic nanobundles are better catalysts for fuel cells than conventional platinum nanoparticles, say US and Chinese scientists. The team made the branched platinum–nickel nanostructures by diffusing Ni species into the crystal lattice of Pt seeds; a method they claim opens a new avenue for the morphology control of bimetallic alloys. The steps and kinks on the nanostructures’ surfaces make them better at oxidising methanol.

Link to journal article
Highly Branched Pt-Ni Nanocrystals Enclosed by Stepped Surface
Z Niu et al
Chem. Sci., 2012, DOI: 10.1039/c2sc00004k

Aromaticity and antiaromaticity is one of the most fundamental concepts of chemistry but the nature of antiaromaticity remains elusive because of the lack of stable species.

A research team from Japan has provided an explanation for why heteroarene-fused boroles are higher in antiaromaticity and benzene-fused boroles are lower in antiaromaticity than the parent borole, providing a crucial design principle for more fascinating antiaromatic π-conjugated molecular systems.

Link to journal article
Heteroarene-fused Boroles: What Governs the Antiaromaticity and Lewis Acidity of the Borole Skeleton?
A Iida, A Sekioka and S Yamaguchi
Chem. Sci., 2012, DOI: 10.1039/c2sc20100c