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The dye-sensitized photoelectrosynthesis cell (DSPEC) integrates high bandgap, nanoparticle oxide semiconductors with the light-absorbing and catalytic properties of designed chromophore–catalyst assemblies. The goals are photoelectrochemical water splitting into hydrogen and oxygen and reduction of CO2 by water to give oxygen and carbon-based fuels. Solar-driven water oxidation occurs at a photoanode and water or CO2 reduction at a cathode or photocathode initiated by molecular-level light absorption. Light absorption is followed by electron or hole injection, catalyst activation, and catalytic water oxidation or water/CO2 reduction. The DSPEC is of recent origin but significant progress has been made. It has the potential to play an important role in our energy future.

Comproportionation reactions of LnX3 (Ln: Sc, Y, La, Gd, Tb, Dy, Ho and X: Cl, Br, I) with the respective rare-earth metals Ln and transition metals M (M: Ru, Rh, Os, Ir, Fe, Co) at 800—1050 °C leads to the formation of 19 new compounds.

Polycrystalline Mx[W6I14] (M: Na, K, Rb, Cs) is prepared by solid state reaction of stoichiometric amounts of MI and W3I12 (

Alkyl- and aryl vinyl sulfones are obtained by eosin Y (EY)-mediated visible-light photooxidation of sulfinate salts and reaction of the resulting S-centered radicals with alkenes.

When treated with dilute inorganic acids N , N ′-diarylhydrazines (hydrazobenzenes) with an alkyl substituent in the 4-position undergo [5,5]-sigmatropic rearrangement reactions to furnish 4-(4′-aminophenyl)-4-alkylcyclohexa-2,5-dienimines ( ipso -benzidines) in moderate to excellent yields. Steric bulk of the 4-alkyl substituent in the starting material decreases the yield of the respective ipso -benzidine. Additional electron-donating alkyl substituents in the ortho - and/or meta -positions on both rings generally promote the reaction and consequently increase the yield of the 4.4′-benzidine rearrangement product. Described herein are our findings regarding the scope and limits of this unusual benzidine rearrangement.

In the presence of a rhodium(II) catalyst, 3,3-disubstituted cyclopropenylmethyl esters that possess an electron-rich or neutral aromatic group undergo isomerization into (acyloxymethylene)cyclopropanes. This transformation, which proceeds with inversion of configuration at the stereogenic center, complements the previously disclosed rearrangement reactions of cyclopropenylmethyl esters. The products arising from this new rhodium-catalyzed rearrangement contain an enol ester group that can be subsequently functionalized to access stereodefined arylcyclopropanes.

An efficient and scalable two-step one-pot procedure for the preparation of cycloalkenes substituted with a functionalized alkyl side chain is reported. This method is based on a triethylborane-mediated iodine atom transfer radical addition (ATRA) of 1-iodoesters and related compounds to methylenecycloalkanes followed by treatment of the intermediate tertiary iodide with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) to promote a selective endo elimination.

First, the potential role of Raman-based techniques in biomedicine is introduced. Second, an overview about the instrumentation for spontaneous and coherent Raman scattering microscopic imaging is given with a focus of recent developments. Third, imaging strategies are summarized including sequential registration with laser scanning microscopes, line imaging and global or wide-field imaging. Finally, examples of biomedical applications are presented in the context of single cells, laser tweezers, tissue sections, biopsies and whole animals.

A new procedure for the oxidation of sulfides to sulfones utilizing heterogeneous ruthenium reagent has been developed. A small amount of ruthenium trichloride (RuCl 3 ) supported on alumina and excess sodium metaperiodate (NaIO 4 ) was used to produce the ruthenium oxidizing catalyst in the reaction mixture. Sodium metaperiodate oxidized the pre-catalyst RuCl 3 to RuO 4 and also maintained a constant supply of RuO 4 by oxidizing lower valent ruthenium ions during the course of the reaction. An environmentally friendly solvent mixture of dimethyl carbonate (DMC) and water was employed. A wide variety of aromatic sulfides were oxidized to sulfones in good to excellent yields by utilizing this procedure.

Covering: 2007 to August 2014 This review highlights recent innovative synthetic strategies developed for the stereoselective construction of natural complex decalin systems. It offers an insight into various synthetic targets and approaches and provides information for developments within the area of natural products as well as synthetic methodology.

The new title compound is prepared by solid state metathesis reaction of MgCl2, GaN, Li3N, and Li3BN2 in the molar ratio of 3:1:1:1 (Nb ampule, 1100 °C, 48 h).

Recent advances regarding the synthetic chemistry of fluorinated aziridines, azetidines, pyrrolidines and their lactam/amino acid counterparts are presented. These heterocycles are of high importance both as building blocks for more complex structures and as active parts of medicinal chemistry-oriented compounds.

Glycolates or glycinates derived from diversely substituted secondary cyclopropenylcarbinols have been involved for the first time in an Ireland–Claisen rearrangement. This reaction allows an efficient and stereoselective access to highly functionalized alkylidenecyclopropanes possessing an α-hydroxy or α-amino acid subunit, which in turn are valuable precursors of substituted cyclopropanes by diastereoselective hydrogenation of the exocyclic alkene.

Ongoing reduction of WCl6 by elemental Fe intercalation successively results in the compounds FexWCl6, FeW2Cl10, Fe2W2Cl10, (Fe,W)1-xCl2, and FeW6Cl14.

Cu[W6CCl18] (I) is obtained by solid state reaction of β-WCl6, Cu, and C6Cl6 (evacuated silica tubes, 700 °C, 2 h; heating and cooling rate of 2 K/min).

The diastereoselective Mannich reaction of functionalized aldehydes, using a phenethylamine-derived iminium precursor, by activation with prolines and prolinol derivatives have been studied. Optimized reaction conditions have been developed, allowing for scale-up and preparation of γ-amino alcohol derivatives on multi-gram scale from β-hydroxypropanal and -butanal, with diastereoselectivites of typically >73:27 and yields of >60 %. After chromatographic diastereoisomer separation, hydrogenolytic debenzylation, enantiomerically pure Fmoc-β2-Ser(tBu)-OH and Fmoc-β2-Thr(tBu)-OH were thus prepared on multi-gram scale in 6 steps and with overall yields of 24 % and 10 %, respectively, starting from commercially available starting compounds.

Thermal scanning of the Mn—W—Cl system reveals the formation of four new compounds, MnxWCl6 (I), MnW2Cl10 (II), (Mn,W)1-xCl2 (III), and MnW6Cl14 (IV) upon progressive reactions of WCl6 and Mn powder (sealed quartz tube, 125—500 °C, 2—21 d).

Electron-deficient ynamides, possessing an ynoate or an ynone moiety, have been successfully involved for the first time in a 1,3-dipolar cycloaddition with stabilized pyridinium ylides. These reactions afford an efficient and general access toward a variety of substituted 2-aminoindolizines which can serve as useful precursors for the synthesis of other more complex nitrogen heterocycles.

The title process gives cycloadducts of limited stability that decompose at ambient temperature.

A formal [2 + 2 + 2] cycloaddition of enynes (I) and (IV) with aliphatic and aromatic aldehydes is achieved in the presence of Ca(NTf2)2 and Bu4NPF6 or Bu4NBF4 as mixed catalyst system resulting in the formation of dihydropyran derivatives (III) and (V).

The diastereoselectivity of the Pictet—Spengler cyclization of bicyclic N-acyliminium ions that contain a 3-azabicyclo[n.3.0]alkane core and an electron-rich π-nucleophilic moiety, such as an indol-2-yl, indol-3-yl, 1-methylpyrrol-2-yl, or 3,5-dimethoxyphenyl group, is examined.

Mg3(BN2)N is prepared by solid state metathesis reaction of a 3:1:2 molar mixture of MgCl2, Mg3N2, and Li3BN2 (evacuated silica tube, 700 °C, 1 d).

ConspectusActivation of unsaturated carbon–carbon bonds by means of transition metal catalysts is an exceptionally active research field in organic synthesis. In this context, due to their high ring strain, cyclopropenes constitute an interesting class of substrates that displays a versatile reactivity in the presence of transition metal catalysts. Metal complexes of vinyl carbenes are involved as key intermediates in a wide variety of transition metal-catalyzed ring-opening reactions of cyclopropenes. Most of the reported transformations rely on intermolecular or intramolecular addition of nucleophiles to these latter reactive species. This Account focuses specifically on the reactivity of carbenoids resulting from the ring-opening of cyclopropenes in cyclopropanation and C–H insertion reactions, which are arguably two of the most representative transformations of metal complexes of carbenes.Compared with the more conventional α-diazo carbonyl compounds, the use of cyclopropenes as precursors of metal ca...

Mg6Al2(BN2)2N4 (I) and Mg7Si(BN2)2N4 (II) are prepared by solid state metathesis reaction (1100 °C) of MgCl2, Li3(BN2), and AlN for (I) and of Mg3N2, BN, and Si3N4 for (II).

Sintered crystallites of nominal composition Ag0.68Pb0.61Bi2.28Se5 are prepared by melting of the elements under Ar (SiO2 tube, 873 K, 10 d).

The new compound W4(PBr)Br10 is obtained by reduction of WBr6 with elemental phosphorus at 450 °C for 72 h and characterized by powder XRD, and solid state MAS 31P NMR spectroscopy.

This paper describes the analysis of the ν 3 and ν 6 fundamental bands of methyl chloride d 3 using a high-resolution spectrum (resolving power of the apparatus: 0.0015 cm −1 ). These bands are coupled by a weak Coriolis interaction and are then treated simultaneously. Spectroscopic constants are derived for the two isotopic species CD 3 35 Cl and CD 3 37 Cl.

Single crystals of the new title compound are prepared by reaction of Ce, CeCl3, and NaN3 in a reactive NaCl flux (850 °C, 7 d).

Secondary enamines generated in situ from imine (I) and diethylphosphate react with aldehydes to give cross-aldol condensation products.

UiO-66 metal-organic framework, modified with catechol-substructures and metalated with Cr provides an efficient, completely recyclable and reusable catalyst for oxidation of alcohols to ketones.

Comproportionation reactions of YI3, Y, and Ni leads to the formation of the title compound (sealed Ta tube in an evacuated silica tube, 1050 °C, 1 week) which is isostructural with the prototypical [RuY6]I10.