Supported and liquid phase task specific ionic liquids for base catalysed Knoevenagel reactions

The effect of transcranial focused ultrasound target location on the acoustic feedback control performance during blood-brain barrier opening with nanobubbles

Real-time acoustic feedback control based on harmonic emissions of stimulated microbubbles may be important for facilitating the clinical adoption of focused ultrasound (FUS)-induced blood-brain barrier (BBB) opening, both to ensure safe acoustic exposures, and to achieve repeatable and consistent opening. Previously our group demonstrated that successful BBB opening was achievable with both commercially available microbubbles and custom-made nanobubbles under acoustic feedback control. In a recent study, we demonstrated the acoustic control performance was not sensitive to the nanobubble concentration within 10⁹–10¹¹ bubbles/ml. The goal of this study was to examine the effect of the ultrasound target location in the rat brain on the acoustic control quality during BBB opening with nanobubbles. Temporal analysis of the received acoustic signals during each ultrasound pulse indicated that stable nanobubble oscillation was present throughout the entire 10 ms ultrasound exposure. The acoustic feedback control signals were very sensitive to the brain spatial location in rats. There appears to be a shared pattern of acoustic control stability in the brain across different animals, suggesting anatomical features are an underlying cause. The findings emphasize the importance of tuning acoustic feedback control algorithms for specific rodent brain regions of interest to ensure optimal performance.

Acidic ionic liquid based UiO-67 type MOFs: a stable and efficient heterogeneous catalyst for esterification

Acidic ionic liquid groups were introduced into the frameworks successfully and the resulting materials showed excellent activity.

Carbon Dioxide Utilisation for the Synthesis of Unsymmetrical Dialkyl and Cyclic Carbonates Promoted by Basic Ionic Liquids

An efficient and greener synthesis of unsymmetrical organic carbonates mediated by Hünig’s base-appended basic ionic liquids, via carbon dioxide conversion, is described here. These ionic liquids were found to be effective bases for the fixation of carbon dioxide by various alcohols and benzyl bromide, at room temperature. When the alcohol and the halide functionalities are present within the same substrate, the reaction cleanly produces a cyclic carbonate. These functionalised basic ionic liquids were fully recyclable with no loss product yields.

An imidazolium based ionic liquid supported on Fe3O4@SiO2 nanoparticles as an efficient heterogeneous catalyst for N-formylation of amines

An ionic liquid supported on silica-coated ferrite nanoparticles as an efficient and reusable catalyst for N-formylation of amines.

Ionic liquid [OMIm][OAc] directly inducing oxidation cleavage of the β-O-4 bond of lignin model compounds

Ionic liquids can effectively induce the transformation of lignin model compounds into aromatic compounds by aerobic oxidation under metal-free conditions.

Ionic liquids as solvents for the Knoevenagel condensation: understanding the role of solvent–solute interactions

The hydrogen bond basicityβof ionic liquids, as demonstrated by the NMR studies and the Kamlet–Taft linear solvation energy relationship, was confirmed to be the dominant solvent descriptor determining the rate of the Knoevenagel condensation.

Nitrogen-Containing Ionic Liquids: Biodegradation Studies and Utility in Base-Mediated Reactions

Several ionic liquids (ILs) were prepared in order to study the susceptibility of various cores and substituents to biodegradability using the ‘CO2 headspace’ test (ISO 14593). Several of the ILs contained tertiary amine substituents and were tested as solvents and reagents for several base mediated processes including Suzuki–Miyaura, Sonogashira, Knoevenagel, and Morita–Baylis–Hilman reactions. It was found that although these ILs contain basic functionality, they do not promote base mediated reactions. Density functional theory molecular calculations confirmed that the protonation of these ILs is energetically unfavourable.

Choline Chloride and Urea Based Eutectic Solvents: Effective Catalytic Systems for the Knoevenagel Condensation Reactions of Substituted Acetonitriles

The Knoevenagel condensation of aromatic aldehydes with active methylene compounds such as malononitrile, ethyl cyanoacetate, benzimidazole-2-acetonitrile and benzothiazole-2-acetonitrile proceeded very smoothly, in a reusable and cheap choline chloride and urea based deep eutectic solvents. Both reaction time and yield are satisfactory. The advantages of this catalyst are that it is readily available, biodegradable, non-toxic, low cost and is recyclable.

Green and Efficient Knoevenagel Condensation Catalysed by a DBU Based ionic Liquid in Water

An efficient, clean and facile protocol for the Knoevenagel condensation of aromatic aldehydes with active methylene compounds catalysed by task specific ionic liquid 1,8-diazabicyclo[5.4.0]-undec-7-en-8-ium acetate in an aqueous medium has been developed. The reactions proceed at room temperature and high to excellent yields were afforded. The workup procedure is very simple. The ionic liquid could be recycled for 10 runs without noticeably loss of its catalytic activity.