Synthesis of [Mo6S8(PEt3)6] by reductive dimerization of a trinuclear molybdenum chloro sulfido cluster complex coordinated with triethylphosphine and methanol: a molecular model for superconducting Chevrel phases

Abstract

ChemInform Abstract The title complex (II) is prepared as shown by reductive dimerization of (I), which is a new class of cluster condensation. (II) crystallizes in the space group R3 with Z=3 and has 20 cluster valence electrons. The cluster possesses a regular octahedral core of six Mo atoms. The cyclic voltammetry and coulometry in CH2Cl2 solution indicate reversible one-electron reduction and oxidation waves.

Synthesis, characterization, and reactivity of sulfided hexanuclear molybdenum cluster compounds

“…Simultaneously, Japanese researchers reported the synthesis of the same cluster using a different procedure [24]. The same average intracluster Mo-Mo bond distance of 2.66Â was found by both sets of workers.…”

“…The facile formation of MoeSg'ôPEtg by the. reduction of Mog8^Cl^(PEtg)^(MeOH) at room temperature adds proof to its thermodynamic stability [24]. The formation of the completely sulfided MogSg GPEtg cluster by the methods used in this research seems to be dependent on the presence of base in the reaction mixture.…”

“…established examples [13]. However, with the recent discovery of MogSg GPEtg, the first example of an isolated cluster of molybdenum with sulfide ligands has been established [23,24].…”

“…A low-temperature route to the binary Chevrel phase, MogSg, has become more realizable since the preparation of the molecular compound MogSg 6PEtg [23,24]. This work reports attempts to prepare the Chevrel phase compound, MogSg, or a ternary phase, MMogSg, by removal of the triethylphosphine ligands of the molecular MogSg 6PEtg compound.…”

“…The clusters, as found in MogCl^g and MMogSg, are generally formed at high temperatures through solid state reaction methods [3,58]; however, the molecular compound, MogSg GPEtg, can also be prepared by the reductive dimerization of Mog8^Cl^(PEtg)^(MeOH) at room temperature [24].…”