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The reaction of oxalic amidines R1–N=C(NHR2)–C(NHR2)=N–R1 with CH3MgX followed by uptake of CO2 results in the formation of the trimeric carbamato complexes [R1–N=C(NR2–COO)–C(NR2COO)=N–R1]3Mg3(THF)6 (2a: R1 = R2 = Ph; 2b: R1 = R2 = p‐tolyl) as the thermodynamically stable final products of the reaction. Their X‐ray crystal structures show that the three metal centres are in a linear arrangement. The central magnesium ion is octahedrally surrounded by six O‐donor atoms of the μ2‐carbamato bridges, while both peripheral magnesium ions are facially coordinated by three O‐donor atoms of the carbamato groups and three THF molecules. This coordination sphere can be considered as a structural model for the active centre in the ribulose‐1,5‐bisphosphate carboxylase/oxygenase enzyme. Compound 2a reacts with ZnCl2 or CoBr2, with CO2 elimination, to form dimeric complexes of the type [X2M(oxalamidinato)MX2][Mg(DMF)6] (M = Zn, Co; X = Cl, Br). X‐ray crystal structure analyses show that the d‐metals are tetrahedrally coordinated. The magnesium‐bromide‐containing intermediates in the formation of 2a and 2b are able to transfer CO2 to acetophenone, thus simulating the CO2 activation step in enzymatic biotin‐dependent carboxylation reactions.

Simultaneous nucleation of gold nanoparticles and polymerization of tyramine has been carried out at an immiscible electrolyte interface. By transferring the gold ion of tetraoctylammoniumtetracloroaurate (TOAAuCl(4)) from the organic to the aqueous phase, a fast homogeneous electron transfer from the tyramine monomer reduces the gold ion. Electropolymerization then proceeds, and gold nanoparticles form. The newly formed nanoparticles act as nucleation sites for the deposition of the oligomers/polymer (and possibly vice versa). This results in gold nanoparticles stabilized in a polytyramine matrix. The size of the nanoparticles is controlled by the concentration of oligomers/polymer in solution. The polymer nanoparticle composite film was analyzed with TEM, XPS, and AFM.

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