Cationic iridium(1) complexes of chiral phosphanodihydrooxazoles were uscd as catalysts for the enantioselective hydrogenation of prochiral N-alkyl and N-aryl imines. The complexes are air-stable crystalline solids that can be readily prepared and are easy to handle. The structures of two complexes were determined by X-ray analysis. For N-alkyl imines of acetophenone, enantiomeric excesses of up to 79% were obtained. Dialkyl ketimines and cyclic imines showed lower reactivity and selectivity. A remarkable dilution effect was observed for the hydrogenation of the N-phenyl imine of acetophenone: decreasing the substrate and catalyst concentration led to a signifi- Keywords

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RfSeH 1 entsteht in einer Eintopfsynthese bei der Reaktion von RfLi [Rf = 2,4,6‐Tris(trifluormethyl)phenyl] mit elementarem Selen und anschließender Umsetzung mit HBF4. Mit 1 konnte zum ersten Mal die Kristallstruktur eines Selenans bestimmt werden. Bei der Umsetzung von 1 mit M[N(SiMe3)2]2 (M = Zn, Pb) im Molverhältnis 2:1 erhält man die Metallselenophenolate Zn(SeRf)2 · HN(SiMe3)2 2 und [Pb(SeRf)2]2 3. 2 kristallisiert als Hexamethyldisilazan‐Addukt, während 3 als Dimer vorliegt.

The unusual pentanuclear lead thiolate cluster Pb5O(SRF)8·2C7H8 (3) (C7H8 = toluene) has been obtained by oxidation of Pb(SRF)2 (2) with dry air and structurally characterized. The central oxygen atom is coordinated to three lead atoms in a trigonal planar fashion. The coordination sphere of the other two lead atoms is completed by coordination of toluene molecules.

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