The synthesis and characterization of a series of molybdenum, iron, ruthenium, nickel, palladium, and platinum complexes containing new achiral and chiral PNP pincer-type ligands based on the N-heterocyclic diamines 2, 6-diaminopyridine, N,N′-di-10-undecenyl-2,6-diaminopyridine, N,N′-dihexyl-2,6-diaminopyridine, and 2,6-diamino-4-phenyl-1,3,5-triazine are reported. The new PNP ligands are prepared conveniently in high yield by treatment of the respective N-heterocyclic diamines with 2 equiv of a variety of achiral and chiral R 2 PCl compounds in the presence of base. Molybdenum PNP complexes of the type [Mo(PNP)(CO) 3 PNP] are obtained by treatment of [Mo(CO) 3 (CH 3 CN) 3 ] with 1 equiv of the respective PNP ligand. They were found to react with I 2 to give novel seven-coordinate pincer complexes of the types [Mo(PNP)(CO) 3 I] + and [Mo(PNP)(CO) 2 (CH 3 CN)I] + depending of whether the reaction is carried out in CH 2 Cl 2 or CH 3 CN. With [Fe(H 2 O) 6 ](BF 4 ) 2 and 1 equiv of PNP ligand in acetonitrile dicationic complexes of the type [Fe(PNP)(CH 3 CN) 3 ](BF 4 ) 2 are obtained. The cis and trans dichloride complexes [Ru(PNP)(PPh 3 )Cl 2 ] are prepared by a ligand exchange reaction of [RuCl 2 (PPh 3 ) 3 ] with a stoichiometric amount of the respective PNP ligand. Cationic PNP complexes of Ni(II), [Ni(PNP)Br]Br, were synthesized by the reaction of [NiBr 2 (DME)] with 1 equiv of PNP ligand. In similar fashion, treatment of [M(COD)X 2 ] (M ) Pd, Pt; X ) Cl, Br) with 1 equiv of PNP ligand yields the cationic square-planar complexes [M(PNP)X]X. If the reaction is carried out in the presence of the halide scavenger KCF 3 SO 3 , complexes of the type [M(PNP)X]CF 3 SO 3 are obtained, which are better soluble in nonpolar solvents than the analogous halide compounds. X-ray structures of representative Mo, Fe, Ru, Ni, and Pd PNP complexes have been determined. Finally, the use of the palladium complexes as catalysts for the SuzukiMiyaura coupling of some aryl bromides and phenyl boronic acid has been examined.

Several new iron(II) complexes of the types [Fe(PNP)(CO)(CH3CN)2]2+, [Fe(PNP)(CO)2Br]+, and Fe(PNP)Cl2 containing tridentate PNP pincer-type ligands have been prepared and characterized. Some of them turned out to be efficient catalysts for the coupling of aromatic aldehydes with ethyldiazoacetate (EDA) to give 3-hydroxyacrylates. These reactions are highly chemoselective, proceed under mild conditions, exhibit good scope, and circumvent the need of slow addition of EDA at low temperature.

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This paper reports a recently finished, interdisciplinary project on rural wastewater management in Austria. The objective of the project was to study alternative wastewater management options based on separation of the wastewater into its constituent parts, and to compare them with conventional ones. Thereby, a feasibility study of both conventional and alternative options for wastewater management in six model regions was carried out. Life cycle costs and social acceptance were analysed by using a case study-based assessment approach. However, hygienic and environmental risks were evaluated on a more general level. In order to complement the findings, a survey on urine separation system users in the Solar City of Linz was conducted. Based on these assessments and empirical findings, the paper concludes that options using a full separation of all wastewater fractions should be considered with care. Options based on a separation of only grey water and black water or in the liquid/solid phase can offer ecological and financial advantages over conventional options. Further, options combining wastewater management and regional biogas plants were identified as an interesting solution. However, legal constraints restrict this option currently.

The paper analyses stress distribution in mono/multi-layers of coated tools. It presents an analysis performed on mono-layer, double-layer and multi-layer coatings using numerical models to detect the developed stress distribution and the most stressed zones in these mostly 1–10 micron layers. With such thin layers, experimental detection of stress distribution would be very difficult. Moreover, coating thickness is distributed differently on flat surfaces from on shaped features in coated tools. This non-uniform coating results solely from the technology applied and such uneven deposition of the coating is critical in terms of how the tools themselves function. The paper provides an analysis of stresses in thinner or accumulated layers of coating on the rounded edge, for example in cutting. This analysis was initiated by ProTech Coating Service, Ltd., which manufactures physical vapour deposition coatings for cutting and forming tools.