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An efficient, mild, and green method was developed for the synthesis of indeno[1,2-b]quinoxaline derivatives via o-phenylenediamine (OPD) and 2-indanone derivatives utilizing β-cyclodextrin (β-CD) as the supramolecular catalyst. The reaction can be carried out in water and in a solid state at room temperature. β-CD can also catalyze the reaction of indan-1,2-dione with OPD with a high degree of efficiency. Compared to the reported methods, this procedure is milder, simpler, and less toxic, making it an eco-friendly alternative. In addition, the β-CD can be recovered and reused without the loss of activity.

Increasing resistance to humid environments is a major challenge for the application of γ-CD-K-MOF (a green MOF) in real-world utilisation. γ-CD-K-MOF–H2S with enhanced moisture tolerance was obtained by simply treating MOF with H2S gas. XPS, Raman and TGA characterizations indicated that the H2S molecules coordinated with the metal centers in the framework. H2S acting as a newly available water adsorption potential well near the potassium centers protects the metal–ligand coordination bond from attack by water molecules and thus improves the moisture stability of MOF. After 7 days exposure in 60% relative humidity, γ-CD-K-MOF–H2S retained its crystal structure and morphology, while γ-CD-K-MOF had nearly collapsed. In addition, the formaldehyde uptake tests indicated that γ-CD-K-MOF retain their permanent porosity after interaction with H2S. This simple and facile one-step strategy would open a new avenue for preparation of moisture stable MOFs for practical applications.

Fibers with good flame retardant (FR) and smoke suppression performances are highly desirable for the purpose of eliminating fire hazard. This study developed a novel FR fiber by wet-spinning poly (vinyl alcohol)/&beta, cyclodextrin (PVA/&beta, CD) composite fiber and crosslinking it with hexamethylene diisocyanate (HDI). &beta, CDs showed good compatibility with PVA matrix, and the resulting PVA/CD/HDI fibers showed mechanical strength at the same level as natural cotton fiber. The PVA/CD/HDI fibers also showed excellent flame retardance (the LOI value of PVA/CD/HDI could reach 41.7%, and their peak of heat release (PHRR) could be reduced by up to 77.7% by neat PVA), and super-smoke suppression (the value of total smoke production (TSP) was only 28.6% compared to PVA). These dramatic reductions of fire hazard were ascribed to the char formation of &beta, CD and crosslinking structure of PVA/CD/HDI, which formed a compact char layer during combustion, thus preventing heat transmission and smoke release.

Increasing resistance to humid environments is a major challenge for the application of γ-CD-K-MOF (a green MOF) in real-world utilisation. γ-CD-K-MOF-H

This paper studies self-assembly of beta-cyclodextrin (beta-CD) and tri-block pluronic (PEG-PPG-PEG) in aqueous solution. It was found that they could form hollow spheres due to the formation of coil-rod beta-CD/PEG-PPG-PEG inclusion complexes. In these beta-CD/PEG-PPG-PEG complexes, the beta-CDs are preferentially stacked along the PPG block of pluronic to form rod block and PEG segments act as coil block. The assemblies of beta-CD/PEG-PPG-PEG complexes show dependence of beta-CDs concentration and temperature. Furthermore, the aggregates will disrupt upon dilution below the critical micelle concentration.

[reaction: see text] The chemoselective ring opening of N-tosyl aziridines with aldehydes catalyzed by an N-heterocyclic carbene was investigated under aerobic conditions. Unexpected carboxylates of 1,2-amino alcohols from the corresponding aldehydes, rather than the acyl anion ring-opened beta-amino ketones, were exclusively obtained. A plausible mechanism for this unprecedented carbene-mediated reaction was also proposed.

Electromagnetic wave absorption coatings can effectively minimize electromagnetic radiation and are widely used in the military and civil field. However, even small scratches on the coating can lead to a large decline of absorption ability and bring serious consequences. To enhance the lifetime of electromagnetic wave absorbing coating, a kind of self-healing electromagnetic wave absorbing coating is developed by introducing host-guest interactions between the absorbing fillers and polymer matrix. After being damaged, the cracks on this coating can be healed completely with the aid of small amounts of water. Simultaneously, the electromagnetic absorbing ability of the coating is restored along with the self-healing process.

This paper presents a kind of thermoresponsive polymeric magnetic particles for protein separations. The magnetofluids were directly encapsulated in hollow particles constructed by self-assembly of rod-coil poly(ethylene glycol)-poly(N-isopropylacrylamide)/α-cyclodextrin (PEG–PNIPAM/α-CD) complexes. The resulting particles showed reversible protein absorption/desorption capacity because the reversible thermo-sensitivity of PNIPAM. Above the lower critical solution temperature (LCST) of PNIPAM, these particles showed high absorptive capacities and adsorption was done at lower temperature. The protein-laden particles are readily removed from the feed solution in a magnetic field.

Background: To manage chemical structures in small laboratories is one of the important daily tasks. Few solutions are available on the internet, and most of them are closed source applications. The open-source applications typically have limited capability and basic cheminformatics functionalities. In this article, we describe an open-source solution to manage chemicals in research groups based on open source and free components. It has a user-friendly interface with the functions of chemical handling and intensive searching. Results: MyMolDB is a micromolecular database solution that supports exact, substructure, similarity, and combined searching. This solution is mainly implemented using scripting language Python with a web-based interface for compound management and searching. Almost all the searches are in essence done with pure SQL on the database by using the high performance of the database engine. Thus, impressive searching speed has been archived in large data sets for no external Central Processing Unit (CPU) consuming languages were involved in the key procedure of the searching. Availability: MyMolDB is an open-source software and can be modified and/or redistributed under GNU General Public License version 3 published by the Free Software Foundation (Free Software Foundation Inc. The GNU General Public License, Version 3, 2007. Available at: http://www.gnu.org/licenses/gpl.html). The software itself can be found at http://code.google.com/p/mymoldb/. (C) 2011 Wiley Periodicals, Inc. J Comput Chem 32: 2942-2947, 2011

Supramolecular biomaterials were prepared based on the formation of partial inclusion complexes between alpha-CD and poly(epsilon-caprolactone) (PCL). Enzyme-catalyzed degradation of these partial alpha-CD-PCL inclusion complexes was investigated at 37 degrees C in the presence of lipase from pancreas porcine. The biodegradation behaviors were monitored by weight loss measurement, (1)H NMR, XRD, GPC, DSC, and SEM. It was found that the formation of inclusion segments significantly accelerated the degradation of materials. A mechanism of enzymatic degradation for partial alpha-CD-PCL inclusion complexes was proposed. The present study provides a preliminary understanding for the biodegradation of the materials constructed by self-assembly between cyclodextrin and polymers.

The first direct asymmetric vinylogous Mannich (AVM) reaction of alpha,alpha-dicyanoolefins and N-Boc aldimines was described promoted by a simple chiral bifunctional thiourea-tertairy amine organocatalyst. The reaction was highly efficient (S/C up to 1000) and regio-, stereoselective (generally99% de, 96 to99.5% ee) at room temperature for a broad array of substrates. Enantiomerically pure delta-amino acid could be smoothly prepared from the adduct.

A highly enantioselective Michael addition of alpha-substituted cyanoacetates to vinyl ketones was accomplished in the presence of simple bifunctional thiourea/tertiary amine organocatalysts. A number of alpha-aryl or alkyl cyanoacetates have been successfully applied to give multifunctional compounds with an all-carbon-substituted quaternary stereocenter in excellent enantioselectivities (82-97 % ee) and yields (61-99 %). The optical pure adducts could be smoothly converted to variously structured beta(2,2)-amino acid esters. Moreover, an interesting reaction model involving multiple hydrogen-bonding interactions amongst the thiourea/tertiary amine catalyst and the reactants has been proposed based on the absolute configuration of the adduct and computational studies.

The title compound, C22H22NP, a kind of Schiff base, which contains soft donor phosphines and hard donor nitro­gen, has been synthesized. The C=N double bond has length 1.253 (2) A. There is a zigzag chain with a di­phenyl­phosphine and a benzene ring.