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Bis(diisopropylamino)cyclopropenimine-substituted bis-protonated proton sponge (BDC) is a useful phase-transfer catalyst for the alkylation of compound (I) with a range of alkyl halides.

Academic and industrial research on nanofibres is an area of increasing global interest, as seen in the continuously multiplying number of research papers and patents and the broadening range of chemical, medical, electrical and environmental applications. This in turn expands the size of the market opportunity and is reflected in the significant rise of entrepreneurial activities and investments in the field. Electrospinning is probably the most researched top-down method to form nanofibres from a remarkable range of organic and inorganic materials. It is well known and discussed in many comprehensive studies, so why this review? As we read about yet another “novel” method producing multifunctional nanomaterials in grams or milligrams in the laboratory, there is hardly any research addressing how these methods can be safely, consistently and cost-effectively up-scaled. Despite two decades of governmental and private investment, the productivity of nanofibre forming methods is still struggling to meet the increasing demand. This hinders the further integration of nanofibres into practical large-scale applications and limits current uses to niche-markets. Looking into history, this large gap between supply and demand of synthetic fibres was seen and addressed in conventional textile production a century ago. The remarkable achievement was accomplished via extensive collaborative research between academia and industry, applying ingenious solutions and technological convergence from polymer chemistry, physical chemistry, materials science and engineering disciplines. Looking into the present, current advances in electrospinning and nanofibre production are showing similar interdisciplinary technological convergence, and knowledge of industrial textile processing is being combined with new developments in nanofibre forming methods. Moreover, many important parameters in electrospinning and nanofibre spinning methods overlap parameters extensively studied in industrial fibre processing. Thus, this review combines interdisciplinary knowledge from the academia and industry to facilitate technological convergence and offers insight for upscaling electrospinning and nanofibre production. It will examine advances in electrospinning within a framework of large-scale fibre production as well as alternative nanofibre forming methods, providing a comprehensive comparison of conventional and contemporary fibre forming technologies. This study intends to stimulate interest in addressing the issue of scale-up alongside novel developments and applications in nanofibre research.

Thermodynamically stable solids M2SiH6 (M: K, Rb) are prepared from mixtures of MH and Si, or MSi using ammonia borane as hydrogen source (NaCl capsule, 4—9 GPa, 400—700 °C, 1 h).

Bromination of 2-acetylfuran with copper(II) bromide in a mixture of ethyl acetate and chloroform leads selectively to furacyl bromide, the nucleophilic substitution of bromine in which by OAc and subsequent use of the Weidenhagen reaction enabled the synthesis of 4(5)-(2-furyl)imidazole. On N-methylation of this imidazole in KOH-acetone 2 isomers are formed, the 1-methyl-4- and 1-methyl-5-(2-furyl)imidazoles. It was established that, unlike alkylation of 4(5)-phenylimidazole, the main product of the reaction is 1-methyl-5-(2-furyl)imidazole.

The title compound is synthesized from mixtures of LiH and Pt in the presence of BH3NH3 (multi-anvil device

The possible thione–thiol tautomerism of 2- and 4-mercaptopyridines, 2-mercaptopyrimidine, and 4,6-dimethyl-2-mercaptopyrimidine in solution is studied by means of absorption (UV–VIS) spectroscopy....

The condensation of diphenic anhydride with o-, m- and p- halogenosubstituted phenylacetic acids gave the respective enolacetates Ia-Ie . The alkaline hydrolysis of these compounds yields the diketones IIa-IIe . After testing blood cloting agents in vivo, the last compounds showed indications of anticoagulants.

Formylation of 4-hydroxy-6-methyl-2(1H)-pyridones and subsequent cyclization with a Wittig reagent or with CH-acidic esters gave a series of title compounds. The same starting pyridones reacted with methyl 3-amino-2-butenoate directly to the corresponding 4,7-dimethylpyrano[3,2-c]pyridines.

A method is described for transforming perfluoroalkanes and perfluorocycloalkanes bearing tertiary fluorine into perfluoroenolates, which can be variously derivatized.

A number of new S-alkylisothiuronium salts were synthesized by reaction of ω-[4-hydroxy(methoxy)aryl]alkyl halides with thiourea. The resulting isothiuronium salts in aqueous solution react with sodium (potassium) halides to form halogen exchange products.

The condensation of 2′-hydroxyacetophenone (1) with aromatic aldehydes (2) in a well closed vessel using microwave irradiation or classical heating at 132 °C, provides a fast and simple method for the liquid-phase synthesis of 2′-hydroxychalcones without formation of by-products. Antiproliferative activity of these compounds were evaluated using MCF-7 cells.

Condensation of 9,10-phenanthrenequinone with 2-furaldehyde and 2-thiophenecarbaldehyde in glacial acetic acid in the presence of ammonium acetate gave 2-(2-furyl)- and 2-(2-thienyl)phenanthro[9,10-d]imidazoles which were converted into the corresponding 1-methyl derivatives. The furan and thiophene rings in the products lose their acidophobic properties. Depending on the conditions, electrophilic substitution reactions in 2-(2-furyl)- and 2-(2-thienyl)phenanthro[9,10-d]imidazoles occur both at the furan (thiophene) and phenanthrene moieties.

Dependent on the reaction time, the three-component condensation of dimethyl acetonedicarboxylate (1), aromatic aldehydes 2, and malononitrile (3) gives rise to 4H-pyran derivatives 5 after reflux for 15 min. Moreover, using excess of benzaldehyde and prolonged heating for 150 min afforded multifunctional cyclohexanone derivatives 8. Different substitution patterns in the phenyl nucleus of 8 can be achieved by condensation of 4H-pyran derivatives 5 with benzaldehydes 2.

The synthesis of novel 1,6-naphthyridines 6 with potential activity against tuberculosis is described using the reaction sequence 246. Depending on the ring N-substitution of the 4-alkylamino-6-methyl-2(1H)-pyridones 1 and 2 the electrophilic attack of the Vilsmeier reagent gives rise to the formation of the exocyclic N-formyl derivatives 3 from 1 and the corresponding 3-carbaldehydes 4 from 2. 1,2-Dihydro-2-imino-7-methyl-1,6(6H)-naphthyridin-5-ones 6a-j are prepared by the Knoevenagel reaction of 4 with CH-acidic nitriles 5. These reactions are carried out using a comparative study of conventional conditions (room temperature or reflux) versus microwave irradiation.