BINOL-Containing Chiral Porous Polymers as Platforms for Enantiorecognition.

The enantioselective discrimination of racemic compounds can be achieved through the design and preparation of a new family of chiral conjugated BINOL-porous polymers (CBPPs) from enantiopure ()- or ()-BINOL derivatives and 1,3,5-(4-phenylboronic acid)benzene or 1,3,5-(4-ethynylphenyl)benzene, 1,3,5-triethynyl-2,4,6-trifluorobenzene, and (4-ethynylphenyl)methane as comonomers following Suzuki-Miyaura and Sonogashira-Hagihara carbon-carbon coupling approaches. The obtained CBPPs show high thermal stability, a good specific surface area, and a robust framework and can be applied successfully in the fluorescence recognition of enantiomers of terpenes (limonene and α-pinene) and 1-phenylethylamine. Fluorescence titration of CBPPs-OH in acetonitrile shows that all Sonogashira hosts exhibit a preference for the ()-enantiomer over the ()-enantiomer of 1-phenylethylamine, the selectivity being much higher than that of the corresponding BINOL-based soluble system used as a reference.

Framework Adaptability and Concerted Structural Response in a Bismuth Metal-Organic Framework Catalyst.

Bismuth metal-organic frameworks (MOFs) as heterogeneous catalysts are scarce, and there is little knowledge on the influence of the MOF features on their resulting activity and behavior. Here, we present the synthesis, characterization, and catalytic activity in the one-pot multicomponent Strecker reaction with ketones of three new MOFs prepared with the combination of indium or bismuth and 4,4',4'',4'''-methanetetrayltetrabenzoic acid. One of them, denoted BiPF-7, is very robust and chemically stable, and demonstrates a high activity in the formation of the desired α-aminonitriles.

Femto- to Millisecond Time-Resolved Photodynamics of a Double-Functionalized Push-Pull Organic Linker: Potential Candidate for Optoelectronically Active MOFs.

The design of improved organic linkers for the further engineering of smarter metal-organic framework (MOF) materials has become a paramount task for a wide number of material scientists. In this report, a luminescent double-functionalized push-pull (electron donor-acceptor) archetype organic molecule, dimethyl 4-amino-8-cyanonaphthalene-2,6-dicarboxylate (MeCANADC), has been synthesized and characterized. The optical steady-state properties of MeCANADC are strongly influenced by the surrounding environment as a direct consequence of its strong charge transfer (CT) character.

Effective Approach toward Conjugated Porous Organic Frameworks Based on Phenanthrene Building Blocks: Metal-Free Heterogeneous Photocatalysts.

This paper reports a simple approach for the preparation of new photo-active conjugated porous polymers (CPPs) based on phenanthrene building blocks with a high Brunauer-Emmett-Teller (BET) surface area. Starting from 2,7-diiodophenanthrene-9,10-dione and its bis-dioxolane derivative with different alkynyl comonomers, we prepared a series of CPPs by C-C Sonogashira-Hagihara coupling activated by microwaves. Moreover, we demonstrated that these functionalized CPPs after hydrolysis to the corresponding diketones show much higher BET surface areas than those obtained directly from the phenanthrene-9,10-dione monomer.

Combining Breath Figures and Supercritical Fluids To Obtain Porous Polymer Scaffolds.

Supercritical fluids technology is a clean methodology to foam polymeric materials. However, this technique provides only the formation of inner porosity, whereas the so-called skin layer is commonly observed at the polymer surface. This article describes a new method for the preparation of outer and inner porous poly(ε-caprolactone) (PCL) scaffolds by combination of supercritical CO (SCCO) foaming and the breath figures technique.

A comprehensive profiling of sulfatides in myelin from mouse brain using liquid chromatography coupled to high-resolution accurate tandem mass spectrometry.

Sulfatides are sulfoglycolipids found in the myelin sheath. The composition ratio of sulfatide molecular species changes with age, and it has also been associated with the pathogenesis of various human central nervous system diseases. However, profiling sulfatides in biological samples is difficult, due to the great variety of molecular species.

First pre-functionalised polymeric aromatic framework from mononitrotetrakis(iodophenyl)methane and its applications.

Starting from mononitrotetrakis(iodophenyl)methane as monomer, we report the preparation of the first pre-functionalised porous aromatic frameworks (PAFs) and their application as supports for organometallic catalysts. Neutral coordinate imino-pyridine Schiff base (PAF-NPy) or chiral bis-amino (PAF-NPro) ligands were obtained by post-synthetic treatment of PAF-NH2 and treated with copper(I) or rhodium(I) to yield the corresponding supported transition-metal catalysts. The as-prepared PAF-NN-M catalysts exhibited activity and selectivity similar to that of the corresponding homogeneous catalysts and were easily removed from reaction media and recycled without loss of activity or selectivity.

Isolation and structural characterization of acrylamide-pyridoxamine adducts.

Pyridoxamine (PM) is an effective inhibitor of the formation of the carcinogen acrylamide (AA) from its precursors in low-moisture model systems. Although AA is widely assumed to act by scavenging carbonyl compounds, no alternative pathways have to date been explored. In this work, we found AA to directly react with PM in a low-moisture acrylamide-pyridoxamine model system heated at 140 °C for up to 40 min.

Enhanced laser action of Perylene-Red doped polymeric materials.

The laser action of Perylene-Red doped in linear, crosslinked, fluorinated and sililated polymeric materials is reported. The purity of dye was found to be a key factor to enhance its solid-state laser behaviour. The samples were transversely pumped at 532 nm, with 5.

Efficient red-edge materials photosensitized by Rhodamine 640.

We report on tunable, highly efficient and photostable solid-state dye laser emitting around 640 nm based on Rhodamine 640 incorporated into homopolymers, linear and cross-linked copolymers, and silicon-modified organic matrices. The effect on the lasing properties of both dye concentration and environmental conditions was analyzed. Under transversal pumping at 532 nm with 5.

New analogues of the BODIPY dye PM597: photophysical and lasing properties in liquid solutions and in solid polymeric matrices.

New tailormade BODIPY dyes have been synthesized by a simple protocol to reach wavelength finely tunable laser action from 540 to 625 nm while maintaining highly efficient and photostable laser emission. The new dyes are analogues of the commercial dye PM597 with the eight position free (PTH8) or substituted by the groups acetoxymethyl (PTAlk) or p-acetoxymethylphenyl (PTAr). The photophysical properties strongly depend on the geometrical distortion from planarity of the indacene core generated by the presence of the bulky 2,6-di-tert-butyl groups and the eight substituent.

Synthesis, photophysical properties, and laser behavior of 3-amino and 3-acetamido BODIPY dyes.

The asymmetrically substituted BODIPY dyes 9a and 9b have been synthesized through a key redox step involving the alpha-nitroso derivative of the starting pyrrol. Both dyes emit fluorescence with quantum yields of ca. 0.