Dynamic Thermodynamic Resolution of Racemic 1,1'-Binaphthyl-2,2'-diol (BINOL).

A dynamic thermodynamic resolution method for converting (/)-BINOL (1,1'-binaphthyl-2,2'-diol) into ()-BINOL in 100% theoretical yield is reported. This technique involves mixing (/)-BINOL with -benzyl cinchonidinium bromide (1 equiv) and a [Cu(tmeda)(μ-OH)]Br (2.5 mol %) redox catalyst in acetonitrile.

A General Electro-Synthesis Approach to Amaryllidaceae Alkaloids.

Amaryllidaceae alkaloids appeal to organic chemists with their attractive structures and their impressive antitumor and acetylcholinesterase inhibitory properties. We demonstrate a highly versatile access to this family of natural products. A general protocol with high yields in a sustainable electro-organic key transformation on a metal-free anode to spirodienones facilitates functionalization to the alkaloids.

Beyond Kolbe and Hofer-Moest: Electrochemical Synthesis of Carboxylic Anhydrides from Carboxylic Acids.

Herein we report a conceptually new non-decarboxylative electrolysis of carboxylic acids to obtain their corresponding anhydrides as highly valuable reagents in organic synthesis. All carbon atoms of the starting material are preserved in the product in an overall redox-neutral reaction. In a broad substrate scope of carboxylic acids the anhydrides are generated with high selectivity, which demonstrates the versatility of the developed method.

Allocolchicines─Synthesis with Electro-organic Key Transformations.

The naturally occurring colchicine and allocolchicines in the meadow saffron are potentially active ingredients for cancer therapy. A concise protocol for the sustainable synthesis of allocolchicines using up to two electro-organic key transformations is demonstrated. This straightforward synthesis of -acetylcolchinol methyl ether in a five-step protocol was adopted using protecting groups to enable access to -acetylcolchinol and the phosphate derivative ZD6126.

Electro-organic synthesis - a 21 century technique.

The severe limitations of fossil fuels and finite resources influence the scientific community to reconsider chemical synthesis and establish sustainable techniques. Several promising methods have emerged, and electro-organic conversion has attracted particular attention from international academia and industry as an environmentally benign and cost-effective technique. The easy application, precise control, and safe conversion of substrates with intermediates only accessible by this method reveal novel pathways in synthetic organic chemistry.

Reproducibility in Electroorganic Synthesis-Myths and Misunderstandings.

The use of electric current as a traceless activator and reagent is experiencing a renaissance. This sustainable synthetic method is evolving into a hot topic in contemporary organic chemistry. Since researchers with various scientific backgrounds are entering this interdisciplinary field, different parameters and methods are reported to describe the experiments.

A Decade of Electrochemical Dehydrogenative C,C-Coupling of Aryls.

The importance of sustainable and green synthetic protocols for the synthesis of fine chemicals has rapidly increased during the last decades in an effort to reduce the use of fossil fuels and other finite resources. The replacement of common reagents by electricity provides a cost- and atom-efficient, environmentally friendly, and inherently safe access to novel synthetic routes. The selective formation of carbon-carbon bonds between two distinct substrates is a crucial tool in organic chemistry.

Aromatic vs. Aliphatic Hyperbranched Polyphosphoesters as Flame Retardants in Epoxy Resins.

The current trend for future flame retardants (FRs) goes to novel efficient halogen-free materials, due to the ban of several halogenated FRs. Among the most promising alternatives are phosphorus-based FRs, and of those, polymeric materials with complex shape have been recently reported. Herein, we present novel halogen-free aromatic and aliphatic hyperbranched polyphosphoesters (hbPPEs), which were synthesized by olefin metathesis polymerization and investigated them as a FR in epoxy resins.

Determination of alpha-tocopherolquinone in human serum samples by liquid chromatography with fluorescence detection and on-line post-column derivatization.

A HPLC/fluorescence method with on-line post-column derivatization by a photoreactor was developed, where alpha-, beta + gamma- and delta-tocopherolquinone (TQ) are separated on a 250 mm x 4.6 mm RP-18 column. The LOD is about 250 pg for all TQs.

Determination of tocopherols, tocopherolquinones and tocopherolhydroquinones by gas chromatography-mass spectrometry and preseparation with lipophilic gel chromatography.

Lipophilic gel chromatography using Sephadex LH-20 helps in separating alpha-, beta- + -gamma, and delta-tocopherol and also in separation of their oxidation products e.g. the tocopherolquinones or other oxidation products.