Novel quasi-aromatic transition metal cluster compounds

Abstract

Abstract From the point of view of chemical reactivities, molecular configurations, and bonding characteristics, a series of novel quasi-aromatic transition metal cluster compounds has been studied in this article. Experimental evidences for the cluster compounds [M3(μ3-X)(μ-y)3]4+ (M = Mo, W; X, Y = O, S, Se, Te) containing a puckered {M3(μ-Y)3}six-membered rings reveal benzene-like structural characteristics and chemical behaviours in a series of ligand substitution, addition, and oxidation reactions. The energy localized CNDO/2 molecular orbital method is applied to elucidate the nature of quasi-aromaticity in this type of cluster compound. The localized molecular orbitals (LMOs) of benzene as an aromatic prototype and a series of planar monocyclic polyene hydrocarbons CnHq n as well as certain typical conjugated six-membered rings are investigated, leading a deep-rooted inherent relationship between their aromaticity and bonding characteristics. The LMO analyses for these cluster compounds with [Mo3(μ...