6533b85dfe1ef96bd12bf0c5

RESEARCH PRODUCT

The preparation of four- and six-membered chalcogenametallacyclic derivatives of group 4 metallocenes

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Abstract Four-membered metallacycles [(RC 5 H 4 ) 2 M(μ-E)] 2 (M = Zr, Hf; 1 , E = Se; 2 , E = S) were obtained by UV irradiation of dialkyl- or diaryl-metallocenes and equimolecular amounts of elemental chalcogen, but this method works only for bulky R groups. A more general route to compounds 1 and 2 involves the reaction of metallocene dichloride with chalcogenide anions. Six-membered metallacyclohexasulfanes (t-BuC 5 H 4 ) 2 MS 5 ( 3 , M = Zr, Hf) are obtained rather than compounds 2 when an excess of sulfur is used in the photolytic experiments, whereas compounds 1 were still formed when an excess of selenium was used. The observed difference is explained in terms of the solubility of the chalcogen in the solvent used for the reaction.