ANIONIC AND NEUTRAL SPIKED TRIANGLE CLUSTERS OF MERCURY - A COMPARATIVE-STUDY OF THE METAL-LIGAND REDISTRIBUTION PROCESS

The action of the NEt+4 salts of the anions [Fe2(CO)8]2- and [Fe2(CO)6(μ-CO)(μ-PPh2)]- on ClHg-m complexes (m = Mo(CO)3Cp, W(CO)3Cp, Mn(CO)5, Co(CO)4, and Fe(CO)2Cp) has been investigated. In the first case, anionic spiked triangle clusters of formula [Fe2(CO)6(μ-CO)2(μ-Hg-m)]- were obtained in high yields, and no metal ligand redistribution reactions were detected. However, the action of [Fe2(CO)6(μ-CO)(μ-PPh2)]- on the same bimetallic transition metal-mercury compounds gave the neutral species [Fe2(CO)6(μ-CO)(μ-PPh2)(μ-Hg-m)], which spontaneously redistributed to [Hg{Fe2(CO)7(μ-PPh2)}2] and m2Hg. Only the molybdenum derivative could be isolated in pure form. The different behaviour of the two series of complexes in the redistribution process is discussed. © 1990.