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The complexes [Pd(acac)2] 1, [Pd(hfa)2] 2 (hfa = hexafluoroacetylacetonate), [Pd(CF3CO2)2] 3 and [Pd3(CH3CO2)6] 4 exhibit very different catalytic efficiency in the reaction between secondary amines and activated alkenes. Complexes 1 and 4 generally show an enhanced activity when catalytic amounts of NH4X salts (X− = low-coordinating anion) are added to the reaction mixtures. On the contrary, the activity of the perfluorurate analogues 2 and 3, which is much higher than that of 1 and 4, is generally scarcely affected by the presence of the NH4X additive. The cocatalytic effect of NH4X is comparable with that of strong acids such as CF3SO3H. The ammonium salts alone can behave as a catalyst giving an almost quantitative yield of the hydroamination product.

The reaction between primary amines (RNH2) and diaryl diazomethanes (Ar2CN2) in the presence of catalytic amounts of the complex [RuCl(η5-C5H5)(PPh3)2] (1), in chloroform at 60 °C, generally affords mixtures of imines Ar2CNR as main product and amines Ar2CHNHR. Whereas Ar2CHNHR are formed by the expected carbene insertion into the NH bond of the substrate, the generation of Ar2CNR is unprecedented. The carbene intermediate [RuCl(CAr2)(η5-C5H5)(PPh3)] seems to be the key-species involved in the formation of both products.

A simple one-step method for the preparation of dinuclear chloro-bridged platinum(II) phosphine complexes, [Pt(μ-Cl)Cl(PR3)]2 is reported. The syntheses are carried out in p-chlorotoluene and are reported for the following tertiary phosphines: PMe2Ph, P(p-Tol)3, PPh3, PBun3 and PEt3.