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A three-part experiment that leads to the synthesis of palladium(II) complex starting from a C3-symmetric triaminoguanidinium-based ligand is presented. In the first part, the preparation of tris-benzylidenetriaminoguanidinium chloride ([H6Br3L]Cl) by an acidic catalyzed 3-fold imine formation reaction of 5-bromo-2-hydroxybenzaldehyde and triaminoguanidinium chloride is described. Starting from the second part, the reaction procedures are performed under inert gas atmosphere. The conversion of PdCl2 with acetonitrile to give [Pd(MeCN)4]Cl2 as a precursor is performed at 80 °C. The third part of the experiment is a three-step procedure that begins with deprotonation of [H6Br3L]Cl, followed by transfer of [Pd(MeCN)4]Cl2 to the reaction flask, where the chelation of Pd(II)-precursor leads to the in situ species [Pd(MeCN)H3Br3L]. Addition of PPh3 as the final reaction step yields [Pd(PPh3)H3Br3L]. This sequence of experiments provides an excellent example of ligand and transition metal preparation and its sub...

Tris-(2-hydroxybenzylidene)triaminoguanidinium salts having six alkyl chains with proper spacing served as new molecular building blocks for the formation of porous honeycomb networks by van der Waals interaction between interdigitated alkyl chains at the liquid/graphite interfaces.

C 3 -symmetric ligands carrying a rigid triaminoguanidinium backbone are important building blocks for the preparation of supramolecular coordination cages as tetrahedra or trigonal bipyramides. Coordination of Eu(III)- or Gd(III)-ions leads to 1,2,4-triazole formation, which has been reported only rarely. Using Pd(II)-complexes as a model system, this triazole formation could be analyzed in more detail. The preparation of Pd(II)-coordination compounds can be easily done under stoichiometric control. These complexes could be transformed into 1,2,4-triazoles using O2 or H2O2 as an oxidation reagent. The steric demand of the PR3-coligand seems to play a key role in the cyclisation reaction.