Straightforward synthesis of chiral sulfonate-based ionic liquids from amino alcohols for chiral recognition.

New sulfonate-based chiral salts were prepared from amino alcohols and sodium hydroxymethanesulfonate, vinyl sulfonate, or sultone. The synthesis started with different amino acids from the chiral pool and gave the desired products in just four steps. After cation metathesis, the salts were explored as chiral solvating agents (CSAs) in NMR studies.

Macromolecular Architecture-Dependent Polymorphous Crystallization Behavior of PVDF in the PVDF/γ-BL System via Thermally Induced Phase Separation.

This study investigates the effect of the macromolecular architecture of poly(vinylidene fluoride) (PVDF) on its thermally induced phase separation (TIPS) behavior and polymorphic crystallization in the PVDF/γ-butyrolactone (PVDF/γ-BL) system. Preparative PVDF fractions with specific macromolecular architecture and phase constitution are generated. The results show that PVDF's macromolecular architecture, particularly the degree of branching and regio-defects, plays a significant role in its temperature-dependent crystallization and resulting polymorphic phases.

Influencing the froth flotation of LiAlO and melilite solid solution with ionic liquids.

In the present work experiments for single mineral flotation against LiAlO and melilite s.s. were carried out for seven ionic liquids (ILs).

Intramolecular Phosphine-Promoted Knoevenagel Based Redox-Reaction.

A Knoevenagel based redox-reaction promoted by intramolecular phosphine sources is presented for the first time. The influence of different diketones, aldehydes, bases and acids was investigated. The effects of different substituents were evaluated based on their electronical influence on the diketone structure.

Reversible functionalization and exfoliation of graphite by a Diels-Alder reaction with furfuryl amine.

Furfuryl amine-functionalized few-layered graphene was prepared a mechanochemical process by a [4 + 2] cycloaddition under solvent-free conditions. By employing ball milling, active sites are merged mostly at the edge of the graphene sheets which makes them prone to Diels-Alder click reactions (D-A) in the presence of a diene precursor. Consequently, one-pot grafting with furfuryl amine onto the graphene sheets, exfoliates pristine graphite resulting in functionalized few-layered graphene which is soluble in organic solvents.

Improvement of the froth flotation of LiAlO and melilite solid solution via pre-functionalization.

In this work froth flotation studies with LiAlO (lithium-containing phase) and Melilite solid solution (gangue phase) are presented. The system was optimized with standard collectors and with compounds so far not applied as collectors. Furthermore, the principle of self-assembled monolayers was introduced to a froth flotation process for the first time resulting in excellent yields and selectivities.

A photoredox catalysed Heck reaction hole transfer from a Ru(ii)-bis(terpyridine) complex to graphene oxide.

The attachment of homoleptic Ru bis-terpy complexes on graphene oxide significantly improved the photocatalytic activity of the complexes. These straightforward complexes were applied as photocatalysts in a Heck reaction. Due to covalent functionalization on graphene oxide, which functions as an electron reservoir, excellent yields were obtained.

Photocatalytic properties of graphene-supported titania clusters from density-functional theory.

Density-functional theory calculations of (TiO ) clusters (n = 1-5) in the gas phase and adsorbed on pristine graphene as well as graphene quantum dots are presented. The cluster adsorption is found to be dominated by van der Waals forces. The electronic structure and in particular the excitation energies of the bare clusters and the TiO /graphene composites are found to vary largely in dependence on the size of the respective constituents.

Straightforward Immobilization of Phosphonic Acids and Phosphoric Acid Esters on Mesoporous Silica and Their Application in an Asymmetric Aldol Reaction.

The combined benefits of moisture-stable phosphonic acids and mesoporous silica materials (SBA-15 and MCM-41) as large-surface-area solid supports offer new opportunities for several applications, such as catalysis or drug delivery. We present a comprehensive study of a straightforward synthesis method via direct immobilization of several phosphonic acids and phosphoric acid esters on various mesoporous silicas in a Dean⁻Stark apparatus with toluene as the solvent. Due to the utilization of azeotropic distillation, there was no need to dry phosphonic acids, phosphoric acid esters, solvents, or silicas prior to synthesis.

Determination of the refractive indices of ionic liquids by ellipsometry, and their application as immersion liquids.

In principle, ionic liquids (ILs) can serve as stable and less harmful high-refractive-index liquids (n>1.60). However, detailed information on their complex refractive indices and dispersions is rare.

A Novel Lubricant Based on Covalent Functionalized Graphene Oxide Quantum Dots.

Dodecyl amine edge functionalized few-layer graphene oxide quantum dots were synthesized in good yields. The covalent functionalization was demonstrated with NMR and AFM-IR. The resulting structure and particle size was measured with AFM and HRTEM.

Influence of Ionic Liquids on an Iron(III) Catalyzed Three-Component Coupling/Hydroarylation/Dehydrogenation Tandem Reaction.

A three-component oxidative dehydrogenation tandem reaction via the coupling and hydroarylation of benzaldehyde, aniline and phenylacetylene to a quinoline derivate was catalyzed by an iron-containing ionic liquid. The reaction was air mediated and could be performed under neat conditions. The iron(III) of the ionic liquid was the oxidizing species.

Crystal structure of tris-(1,3-dimesityl-4,5-di-hydro-1H-imidazol-3-ium) tetra-bromido-cobaltate(II) bromide chloro-form hexa-solvate.

In the unit cell of the title compound, (C21H27N2)3[CoBr4]Br·6CHCl3, the tetrabromidocobaltate(II) anion and the bromide anion are located on a crystallographic threefold rotation axis. For the [CoBr4](2-) group, the axis runs through one of the Br ligands and the Co(II) atom. All other structure moieties lie on general sites.

Crystal structure of di-bromido-bis-(1,3-dibenzyl-1,3-diazinan-2-one-κO)cobalt(II).

The unit cell of the title complex, [CoBr2(C18H20N2O)2], contains 1.5 formula units per asymmetric unit with one mol-ecule sitting on a general site and a second one halved by a crystallographic twofold rotation axis passing through the Co(II) cation. Both Co(II) atoms are coordinated in a distorted tetra-hedral manner by two Br(-) ligands and two O atoms of the pyrimidinone (OPyr) groups.

Crystal structures of di-iodido-bis-[(1S,5S)-4-mesityl-1,2,8,8-tetra-methyl-2,4-di-aza-bicyclo-[3.2.1]octan-3-yl-idene-κC (3)]palladium(IV) and di-chlorido-[(1S,5S)-4-mesityl-1,2,8,8-tetra-methyl-2,4-di-aza-bicyclo[3.2.1]octan-3-yl-idene-κC (3)](tri-phenyl-phosphane-κP)palladium(IV).

The mol-ecular structures of the chiral title compounds, [Pd(C19H28N2)2I2], (I), and [Pd(C19H28N2)Cl2(C18H15P)], (II), show a distorted square-planar coordination around the Pd(II) atoms with two halogenide (Hal) ligands each and two N-heterocyclic carbene (NHC) ligands in (I) or one NHC and one tri-phenyl-phosphane ligand in (II). The deviations of the Pd(II) atoms from the L 2Hal2 best plane (L = NHC or tri-phenyl-phosphane ligand) are 0.206 (1) Å for (I) and 0.

Imidazolinium and amidinium salts as Lewis acid organocatalysts.

The application of imidazolinium and amidinium salts as soft Lewis acid organocatalysts is described. These salts were suitable catalysts for the activation of unsaturated thioesters in a Diels-Alder reaction and in the ring opening of thiiranes and epoxides. The products were isolated in good yields.

New enantiopure NHCs derived from camphor.

A new class of enantiopure carbene precursors based on cheap camphor has been developed, and a restricted rotation of one N-substituent due to the C-10 methyl group of the camphor skeleton has been found; in situ prepared corresponding carbenes revealed the same behaviour.

Hindered Brønsted bases as Lewis base catalysts.

KHMDS and KOtBu are well established as strong, hindered, non-nucleophilic Brønsted bases. However, in the present work these bases are applied as highly active Lewis base catalysts for the formal [2+2] cycloaddition of ketenes with aldehydes and imines.

Enantiopure imidazolinium-dithiocarboxylates as highly selective novel organocatalysts.

Asymmetric imidazolinium-dithiocarboxylates have been found for the first time to be highly selective catalysts; in the present case, the novel organocatalysts were able to catalyze the Staudinger reaction in up to 96% ee and 99% yield.

Lewis acid organocatalysts.

Abstract The term Lewis acid catalysts generally refers to metal salts like aluminium chloride, titanium chloride and zinc chloride. Their application in asymmetric catalysis can be achieved by the addition of enantiopure ligands to these salts. However, not only metal centers can function as Lewis acids.

Unexpected behaviour of tosylated and acetylated imidazolinium salts.

Tosylated and acetylated imidazolinium salts revealed an unexpected reactivity when treated with methyl iodide or benzyl bromide. Moreover an unprecedented acid-catalysed rearrangement for an acetylated imidazolinium salt was observed during an anion metathesis.

Imidazolinium salts as catalysts for the aza-Diels-Alder reaction.

Various easily accessible imidazolinium salts have been found to be capable of catalysing an aza-Diels-Alder reaction with a range of imines and Danishefsky's diene, giving the desired products in good to excellent yields. The influence of the counter-anions on the reactivity has been explored. These salts could contribute to the field of metal-free catalysis/organocatalysis.