Anomalous diffusion of Ibuprofen in cyclodextrin nanosponge hydrogels: an HRMAS NMR study

• Monica Ferro,
• Franca Castiglione,
• Carlo Punta,
• Lucio Melone,
• Walter Panzeri,
• Barbara Rossi,
• Francesco Trotta and
• Andrea Mele

Beilstein J. Org. Chem. 2014, 10, 2715–2723, doi:10.3762/bjoc.10.286

• dynamic regimes is triggered by the polymer structure. CDNSEDTA 1:4 is characterized by a nanoporous structure able to induce confinement effects on IP, thus causing subdiffusive random motion. CDNSEDTA 1:8 is characterized not only by nanopores, but also by dangling EDTA groups ending with ionized COO

• )2 to achieve sufficient contrast. The picture clearly illustrates the porous morphology of the material and the structural heterogeneities in the pore size distribution. Confinement effects are expected to drive the diffusion process from normal to subdiffusive behaviour and interaction with the

• observed on IP in CDNSEDTA 1:8 can be rationalized as a complex balance of the confinement effects and the electrostatic acceleration, with the latter dominating on the former. As a final remark, we mention that the pH variations occurring during the preparative steps affording the drug-loaded hydrogels

Continuous flow nitration in miniaturized devices

• Amol A. Kulkarni

Beilstein J. Org. Chem. 2014, 10, 405–424, doi:10.3762/bjoc.10.38

• -dimethyl-4-nitropyrazole (31) and 3-ethyl-4-nitropyrazole (32) were obtained with nitrating mixture and were expected to show detonating properties under severe confinement (Scheme 9). This flow synthesis did not allow the pressure inside the reactor to undergo rapid variations in a short time, thereby

Spin state switching in iron coordination compounds

• Philipp Gütlich,
• Ana B. Gaspar and
• Yann Garcia

Beilstein J. Org. Chem. 2013, 9, 342–391, doi:10.3762/bjoc.9.39

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• faster at neutral pH values and higher molecular weight polymers were produced in miniemulsion compared to solution polymerization as a result of the confinement effect. The same group carried out a similar study with the copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid and 2

• surfactant, cubic nanoparticles were produced instead of the spherical shells (Figure 9). Only irregular structures were obtained in control experiments performed in water, i.e., without oil nanodroplets. The authors deduced that the initial confinement of the coordination polymerization hence played a

Hybrid biofunctional nanostructures as stimuli-responsive catalytic systems

• Gernot U. Marten,
• Thorsten Gelbrich and
• Annette M. Schmidt

Beilstein J. Org. Chem. 2010, 6, 922–931, doi:10.3762/bjoc.6.98

• of an active catalyst, and ideally can be limited, if necessary, to a geometrical confinement. By controlling the catalytic activity of a particulate carrier by a switchable stimulus, the reaction rate of the catalysed process can be significantly accelerated or slowed down. One promising stimulus in

Self-assembled ordered structures in thin films of HAT5 discotic liquid crystal

• Piero Morales,
• Jan Lagerwall,
• Paolo Vacca,
• Sabine Laschat and
• Giusy Scalia

Beilstein J. Org. Chem. 2010, 6, No. 51, doi:10.3762/bjoc.6.51

• important observation is that the large-scale order is retained. The increase in the temperature range of the ordered state is an effect of the confinement of the molecules into a very thin structure, analogous to the observations made in liquid crystal confined in electrospun polymeric microtubules [14

• ]. Moreover, the spatial confinement gives also stabilization of the alignment. Indeed, after heating the spin-coated sample to the isotropic phase and then cooling it to the LC state, the original alignment was preserved and the texture appeared unchanged from the initial state, in contrast to the

Coaxial electrospinning of liquid crystal-containing poly(vinylpyrrolidone) microfibres

• Eva Enz,
• Ute Baumeister and
• Jan Lagerwall

Beilstein J. Org. Chem. 2009, 5, No. 58, doi:10.3762/bjoc.5.58

• (vinylpyrrolidone) with the liquid crystal 4-cyano-4′-octylbiphenyl in its smectic phase as core material could be produced. The encapsulation leads to remarkable confinement effects on the liquid crystal, inducing changes in its phase sequence. We conducted a series of experiments to determine the effect of

• application of electric and/or magnetic fields, on the other the strong confinement that can be achieved by the process can affect the LC phase sequence [14]. Electrospinning offers a cheap and simple way of studying such confinement effects systematically. In this work we present our results on composites of

• thermogram of bulk 8CB for comparison. The effect of confinement on the LC phase sequence can be clearly seen. In the fibres the clearing peak is broadened and shifted towards higher temperatures compared to the bulk LC, but between the different fibres the clearing point variations are small. The smectic to