Anionic and neutral spiked triangle clusters of mercury: a comparative study of the metal ligand redistribution process

Abstract

The action of the NEt + 4 salts of the anions [Fe 2(CO) 8] 2− and [Fe 2(CO) 6(μ-CO)(μ-PPh 2)] − 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 [Fe 2(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 [Fe 2(CO) 6(μ-CO)(μ-PPh 2)] − on the same bimetallic transition metal-mercury compounds gave the neutral species [Fe 2(CO) 6(μ-CO)(μ-PPh 2)(μ-Hg-m)], which spontaneously redistributed to [Hg{Fe 2(CO) 7(μ-PPh 2)} 2] and m 2Hg. 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.