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Different synthetic approaches and modifications to reaction media have been applied in order to find new routes to the synthesis of main-group clusters and transition metal compounds. The focus has been on the Group 15 element bismuth and the transition metal palladium. The reactions performed have mainly been Lewis acid-base reactions and the characterization tools used X-ray diffraction and Raman spectroscopy.

The Bi₅[GaCl₄]₃ salt, previously known form synthesis using other reaction routes, has been isolated from GaCl₃-dichloromethane media. The salt containing the subvalent naked bismuth polycation Bi₅³⁺ was isolated from the reduction of bismuth(III) chloride. Quantum chemical calculations on the interaction energies of the isolated bismuth cluster show the dichloromethane-cluster interaction energy to be higher than that between benzene and the cluster.

Ionic liquids have, in addition to dichloromethane, been shown to work as alternative reaction media for room-temperature synthesis of the Bi₅[GaCl₄]₃ salt. Three different classes of ionic liquids have been used; phosphonium-, imidazolium- and pyrrolidinium-based salts. The ionic liquids used have been treated with Lewis acids in order to promote cluster formation.

In this work three new palladium sandwich compounds have also been isolated, using GaCl₃-arene reaction media; [Pd₂(Ga₂Cl₇)(C₇H₈)₂], [Pd₂(GaCl₄)(C₉H₁₂)2]∙C₉H₁₂ and [Pd₂(Ga₂Cl₇)(C₆H₅Cl)₂]. Quantum chemical calculations on these palladium sandwiches show the chlorobenzene sandwiching ligands unexpectedly interacting more strongly with the dipalladium unit than the methyl substituted arenes.