The dicationic Ni(II) complex [Ni(Pigiphos)(THF)](ClO4)2, [1](ClO4)2 ((R)-(S)-Pigiphos = bis-{(R)-1-[(S)-2-(diphenylphosphino)ferrocenyl]ethyl}cyclohexylphosphine), catalyzes the addition of bulky aliphatic secondary phosphines to methaacrylonitrile. This hydrophosphination reaction reaches TON = 900 and enantioselectivities up to 94%. A catalytic cycle involving 1,4-conjugate addition of R2PH to methacrylonitrile is supported by the isolation and characterization of a catalytically active N-coordinated, methacrylonitrile Ni complex.

Bis(2-pyridylimino)isoindolato (BPI) ligands, containing an alkynyl linker unit which allows their fixation to carbosilane dendrimers and dendrons, were synthesized by reaction of 4-nitrophthalodinitrile with 4-butynol giving the phthalodinitrile derivative containing the linker. These were subsequently reacted with two molar equivalents of 2-amino-4-methylpyridine and 2-amino-4-(t)butylpyridine yielding the respective BPI protioligands 2a and 2b. Lithiation with LDA and reaction with Si-Cl or Si-OTf (OTf=triflate) end groups in core or peripheral positions of dendritic carbosilanes gave the endodendrally and expdendrally functionalized dendrimers. Among these the first and second generation dendrimers [G-1](8-exo)-4-[C[triple bond, length as m-dash]CCH2CH2O]-10-MeBPI (8), [G-1]12-exo-4-[C[triple bond, length as m-dash]CCH2CH2O]-10-MeBPI (9) and [G-2](16-exo)-4-[C[triple bond, length as m-dash]CCH2CH2O]-10-MeBPI (10) were synthesized and fully characterized. The functional dendrimers were metallated by reaction with [(PhCN)2PdCl2] in dichloromethane to give the corresponding pallada-dendrimers.

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Quaternisi Anäloga der Antiseptica Octafoniumchlorid und = erung des Si‐Derivats (I) mit Benzylchlorid (II) . ergibt das Disilaoctafoniumchlortid (IIIa); das Octafciniurnchlorid (IIIb)Awird nach Lite‐ "ratur dargestellt." Metallierung des Trimethylsilylphenols (IV) mit NaNH2 und an? schließende Umsetzung mit den Chlorarninen (V) geben die tertiären Amine (VI), die niumsalzen (VIII) quaternisiert mit (II) bzwÄMeCl (VII) zu den entsprechenden Ammo‐ h werden.