The cage compound [DippP5 Cl][GaCl4 ] (Dipp=2,6-diisopropylphenyl) reacts with an NHC (N-heterocyclic carbene) by an unprecedented [3+2] fragmentation of the P5 (+) core. This yields an imidazoliumyl-substituted P3 species featuring a triphosphaallyl anion motif and a neutral P2 compound. The mechanism of the fragmentation reaction was elucidated by means of experimental and quantum chemical methods.

Bifunctional mesoporous silica nanoparticles (MSNs) bearing Pd-complexes and additional basic sites were prepared and tested as cooperative active catalysts in the Tsuji-Trost allylation of ethyl acetoacetate. Functionalization of the MSNs was realized by postmodification using click-chemistry. The selectivity of mono versus double allylation was achieved by control of reaction temperature and the nature of the catalyst.

Die Käfigverbindung [DippP5Cl][GaCl4] (Dipp=2,6‐Diisopropylphenyl) reagiert mit einem N‐heterocyclischen Carben (NHC) über eine ungewöhnliche [3+2]‐Fragmentierung des P5+‐Kerns. Die Reaktion liefert eine Imidazoliumyl‐substituierte P3‐Spezies mit Triphosphaallyl‐Motiv und eine neutrale P2‐Verbindung. Der Mechanismus der Fragmentierung wurde mit experimentellen und quantenchemischen Methoden aufgeklärt.

Bifunctional mesoporous silica was prepared by co-condensation of tetraethyl orthosilicate (TEOS) with functionalized organosilanes containing azides or alkoxyamines. Orthogonal functional groups at the particles were selectively addressed in subsequent chemical modifications through "click"-chemistry ("click to ligand" strategy) and radical nitroxide exchange. Palladation with PdCl delivered Pd nanoparticle-loaded silica material bearing sulfoxides and additional aminoamides as stabilizing ligands by means of in situ reduction of the Pd -salt. These functional particles were successfully applied to the hydrogenation of alkynes and alkenes. Aldehyde hydrodeoxygenation and benzyl ether cleavage were achieved with these hybrid catalysts under mild conditions. Particles were analyzed by IR, TEM/STEM, EDX, and solid-state NMR spectroscopy.

Dedicated to Professor Peter Kündig on the occasion of his 75th birthday. 1,2,4,5-Tetrakis(trimethylsilylethynyl)benzene reacted with two molar equivalents of the boranes RÀ B(C 6 F 5 ) 2 (R = C 6 F 5 , Me, Ph) in a series of sequential 1,1-carboboration reactions to give ca. 1 : 1 mixtures of the two-fold benzannulated products, namely the respective C 2h and C 2v symmetric tetra-silyl, bis-boryl substituted anthracenes. Their active B(C 6 F 5 ) 2 substituents were used for consecutive Suzuki-Miyaura CÀ C coupling reactions to give boron-free phenyl or 2-pyridyl substituted anthracene products.

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A monofunctionalized mesoporous silica immobilized Pd‐catalyst is demonstrated to efficiently catalyze the Suzuki coupling of aryl iodides and bromobenzene, but not of chlorobenzene.

A bifunctional heterogeneous palladium catalyst bearing additional basic sites was successfully prepared by sequential Cucatalyzed 1,3-dipolar alkyne-azide cycloaddition and thermal nitroxide-exchange reaction of surface-bound alkoxyamines. This catalyst shows high activity in the Suzuki-Miyaura cross-coupling. The additional basic functionality acts cooperatively since an analogous heterogeneous Pd catalyst lacking the amine functionality is less active. Such catalysts can be recycled up to ten times without loss of activity.