An efficient one-pot procedure was designed by integration of the pincer-complex-catalyzed borylation of allyl alcohols in the Petasis borono-Mannich reaction and in allylation of aldehydes and ketones. These procedures are suitable for one-pot synthesis of alpha-amino acids and homoallyl alcohols from easily available allyl alcohol, amine, aldehyde, or ketone substrates. In the presented transformations, the active allylating agents are in situ generated allyl boronic acid derivatives. These transient intermediates are proved to be reasonably acid-, base-, alcohol-, water-, and air-stable species, which allows a high level of compatibility with the reaction conditions of the allylation of various aldehyde/ketone and imine electrophiles. The boronate source of the reaction is diboronic acid or in situ hydrolyzed diboronate ester ensuring that the waste product of the reaction is nontoxic boric acid. The regio- and stereoselectivity of the reaction is excellent, as almost all products form as single regio- and stereoisomers. The described procedure is suitable to create quaternary carbon centers in branched allylic products without formation of the corresponding linear allylic isomers. Furthermore, products comprising three stereocenters were formed as single products without formation of other diastereomers. Because of the highly disciplined consecutive processes, up to four-step, four-component transformations could be performed selectively as a one-pot sequence. For example, stereodefined pyroglutamic acid could be prepared from a simple allyl alcohol, a commercially available amine, and glyoxylic acid in a one-step procedure. The presented method also grants an easy access to stereodefined 1,7-dienes that are useful substrates for Grubbs ring-closing metathesis.

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Aminoalkylphosphine C6H6HPCH2 · CH2X (X = NH2), N(CH3)2, ; (C6H5)2PCH2 · CH2 · CH2X (X) = NH2, N = CHC6H5, NHC(S)NHC6H5) – reagieren unter geeigneten Bedingungen mit Nickelsalzen zu Koordinationsverbindungen des Typs NiX2 und NiX2()2. Im Falle der PH‐funktionellen ‐Liganden bilden sich unter Abspaltung von HX auch Phosphid‐amininnerkomplexe . Chelataktivität der ‐Liganden sowie Struktur und Eigenschaften der Koordinationsverbindungen werden diskutiert.

Citrate-stabilized palladium nanoparticles with a mean diameter of 13 nm were synthesized in aqueous solution. These particles were utilized as catalysts to grow epitaxial silicon nanowires by chemical vapor deposition at temperatures below 500 °C. The resulting nanowires have a mean diameter of 15 nm. It is found that during the growth process the palladium particles transform into dipalladium silicide.

Der Einfluß der äquatorialen Ligandsubstituenten R, R1 und R2 auf die Tendenz diamagnetisch‐planarer Nickel(II)‐chelate der Typen I, II und III zur Bildung paramagnetischer, oktaedrischer Bis(addukte) mit Pyridin wird durch spektrophotometrische und (zum Teil) magnetische Bestimmung der Gleichgewichtskonstanten (und thermodynamischer Daten) für das Gleichgewicht (1) untersucht. Einige neue Verbindungen der Typen I und II werden synthetisiert und durch sichtbare sowie 1HNMR‐Spektren charakterisiert. Unterschiedliche Methoden zur Auswertung der photometrischen Messungen bei einfachen Gleichgewichten werden verglichen. In Abhängigkeit von den Ligandsubstituenten variieren die K‐Werte von < 10−4 bis > 105 l2 mol−2. Der ausgeprägte Einfluß der peripheren Substituenten R1/R2 korreliert mit ihrem induktiven Effekt. Die N‐Substituenten wirken hauptsächlich auf die Feldstärke der äquatorialen Liganden.