N-Acylamidines 2 are easily prepared by acylation of amidines 1. Upon treatment with PdCl(2)(PhCN)(2), they form 2:1 PdCl(2) complexes 3 with trans configuration, acting as monodentate ligands via the nitrogen atom remote from the carbonyl group. The structures of the complexes 3a-c in the solid state were obtained by X-ray crystallography. As studied by DFT calculations on 2:1 model complexes, many isomeric structures 6 with different conformations and configurations are associated with local minima on the energy hyperface within an energy range of 4 kcal/mol. The complexes 3 show very high catalytic activity in Suzuki-Miyaura cross-coupling reactions, either as isolated crystals or prepared in situ without isolation.

The reaction of N‐pivaloylbenzamidine (1a) and tetrakis(acetonitrile)copper(I) hexafluorophosphate in the presence of air yields a hydroxo‐bridged copper(II) complex (4). The product was characterised by X‐ray diffraction analysis and found to be a cubane‐like dimeric complex consisting of two square dimers with the formula [{(1a)2Cu2(OH)2}2](PF6)4·4 CH2Cl2 (4·4 CH2Cl2) with cupric ions and hydroxyl oxygen atoms at alternating vertices of a cube. The complex can be described as consisting of two [ligand‐Cu‐(OH)2‐Cu‐ligand] units held together by long out‐of‐plane Cu–O bonds, creating a tetrameric entity with a Cu4(OH)4 core. Each cupric ion is essentially square‐pyramidally coordinated, being bound to three OH bridges, one N atom of the amidine and one N‐acylamidine O atom. The magnetic properties of this compound have been studied in the 2–300 K temperature range. The measurements revealed that the cupric ions in the cube are antiferromagnetically coupled. This observation has been rationalised on the basis of the structural data. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

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„Hochreaktive Mehrfachbindungssysteme”︁ stehen seit neun Jahren im ersten Graduiertenkolleg des Fachbereiches Chemie und Pharmazie der Universität Münster im Zentrum der Forschung und Ausbildung von Doktoranden. Zum diesjährigen internationalen Symposium des Graduiertenkollegs am 11. und 12. Oktober 2001 unter dem Titel „Frontiers in Chemistry”︁ waren Wissenschaftler aus Frankreich, der Schweiz, den USA und Japan der Einladung zu Plenarvorträgen nach Münster gefolgt. Daneben präsentierten Kollegiaten des Münsterschen und anderer Graduiertenkollegs ihre neuesten Forschungsergebnisse auf über 30 Postern. Zu den sehr gut besuchten Vorträgen und Postersitzungen waren auch zahlreiche Teilnehmer von anderen deutschen Universitäten und aus der Industrie angereist.