Search

The carbonyl cluster compound [GeRu6(CO)18HI] is unique in regard to its structure and bonding with a GeRu6 cluster core, a planar GeRu4HI unit, extensive multi‐center bonding, and an aromatic ring current similar to benzene (9‐10 nA T−1). The open‐shell cluster core is a Ge‐centered five‐membered Ru4(Ru2) ring with CO ligands and an additional H and I atom, each bridging two Ru atoms on opposite sides of the cluster core. The compound is prepared at 130 °C in a weakly‐coordinating ionic liquid. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report on the synthesis and characterization of a series of (mostly) air‐stable diorganyl bis(pyridylimino) isoindolide (BPI) aluminum complexes and their chemistry upon visible‐light excitation. The redox non‐innocent BPI pincer ligand allows for efficient charge transfer homolytic processes of the title compounds. This makes them a universal platform for the generation of carbon‐centered radicals. The photo‐induced homolytic cleavage of the Al−C bonds was investigated by means of stationary and transient UV/Vis spectroscopy, spin trapping experiments, as well as EPR and NMR spectroscopy. The experimental findings were supported by quantum chemical calculations. Reactivity studies enabled the utilization of the aluminum complexes as reactants in tin‐free Giese‐type reactions and carbonyl alkylations under ambient conditions, which both indicated radical‐polar crossover behavior. A deeper understanding of the physical fundamentals and photochemical process was provided, furnishing in turn a new strategy to control the reactivity of bench‐stable aluminum organometallics. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of a novel ferrocenyl‐functionalized bis(phosphinimino)methane ligand (CH2(PPh2NFc)2). Deprotonation of CH2(PPh2NFc)2 with KN(SiMe3)2 gave the dimeric species [K{CH(PPh2NFc)2}]2, which was further reacted with ECl2 (E=Ge, Sn) to yield the tetrylene compounds [{CH(PPh2NFc)2}ECl]. The ligand and the resulting tetrylenes were examined for their electrochemical properties with the aid of cyclic voltammetry. Furthermore, the reaction of the tetrylenes [{CH(PPh2NFc)2}ECl] with [AuC6F5(tht)] resulted in the bimetallic complexes [{(AuC6F5)CH(PPh2NFc)2}ECl] with an unusual Au coordination on the ligand backbone. [ABSTRACT FROM AUTHOR]

We report on so‐called "hidden FLPs" (FLP: frustrated Lewis pair) consisting of a phosphorus ylide featuring a group 13 fragment in the ortho position of a phenyl ring scaffold to form five‐membered ring structures. Although the formation of the Lewis acid/base adducts was observed in the solid state, most of the title compounds readily react with carbon dioxide to provide stable insertion products. Strikingly, 0.3–3.0 mol% of the reported aluminum and gallium/carbon‐based ambiphiles catalyze the reduction of CO2 to methanol with satisfactory high selectivity and yields using pinacol borane as stoichiometric reduction equivalent. Comprehensive computational studies provided valuable mechanistic insights and shed more light on activity differences. [ABSTRACT FROM AUTHOR]

We report the isolation and characterization of an unknown reaction product from the reaction of AlBr3 with three equivalents of t‐BuLi. The polymeric and solvent‐free lithium alanate {Li[t‐Bu2AlH2]}n was characterized by X‐ray structure analysis, NMR and IR spectroscopy. The title compound was found to be a suitable starting material for the synthesis of [t‐Bu2AlH]3 by reacting it with readily available [t‐Bu2AlBr]2. [ABSTRACT FROM AUTHOR]

The synthesis of three novel imidazolyl‐substituted sulfur‐containing heteroacenes is reported. These heteroacenes consisting of annelated benzo‐ and naphthothiophenes serve as precursors for the generation of open‐shell quinoid heteroacenes by oxidation with alkaline ferric cyanide. Spectroscopic and computational experiments support the formation of reactive open‐shell quinoids, which, however, quickly produce paramagnetic polymeric material. [ABSTRACT FROM AUTHOR]

The rare earth element complexes (Ln=Y, La, Sm, Lu, Ce) of several podant κ6N‐coordinating ligands have been synthetized and thoroughly characterized. The structural properties of the complexes have been investigated by X‐ray diffraction in the solid state and by advanced NMR methods in solution. To estimate the donor capabilities of the presented ligands, an experimental comparison study has been conducted by cyclic voltammetry as well as absorption experiments using the cerium complexes and by analyzing 89Y NMR chemical shifts of the different yttrium complexes. In order to obtain a complete and detailed picture, all experiments were corroborated by state‐of‐the‐art quantum chemical calculations. Finally, coordination competition studies have been carried out by means of 1H and 31P NMR spectroscopy to investigate the correlation with donor properties and selectivity. [ABSTRACT FROM AUTHOR]

The synthesis and full characterization of novel 1,1′‐difunctionalized ferrocene metalloligands is described. While one cyclopentadienyl ring has been functionalized with 2,2′‐bipyridine for secondary coordination, the second Cp ring has been decorated with different aryl moieties containing electron withdrawing groups such as 4‐(CF3)C6H4 (2A) 3,5‐(CF3)2C6H3 (2B) or 4‐(NO2)C6H4 (2C). The newly developed metalloligands were reacted with [Pd(cod)Cl2] (3A–C), CuCl2 (4A–C) and trans‐[(PPh3)2Ni(Mes)Br] (5A,B) to obtain the corresponding square‐planar and dimeric square‐pyramidal complexes. The electrochemical behaviour of the ligands and complexes was investigated with the aid of cyclic voltammetry and compared with the corresponding monofunctionalized derivatives. The influence of the implemented functional groups on the nickel complexes was then confirmed for the reductive elimination reaction of an aryl ether induced by oxidation of the corresponding methoxides (6A,B,D). The experimental findings are supported by quantum chemical calculations. [ABSTRACT FROM AUTHOR]