MIXED FE MO MIXED-CHALCOGENIDE HOUR-GLASS CLUSTERS, [FE4MO(CO)(14)(MU(3)-E)(2)(MU(3)-E')2] AND [FE3MO(CO)(11)(MU(3)-E)(MU(3)-E')-(MU-E'-E')] (E, E' = S, SE OR TE)/

The room-temperature reactions of [Fe-2(CO)(6)(mu-EE')] (EE' = SeTe, S Te, SSe, S-2 or Se-2) with [Mo(CO)(5)(thf)] (thf = tetrahydrofuran) yi elded two types of mixed-metal, mixed-chalcogenide 'hour-glass' cluste rs: [Fe4Mo(Co)(14)(mu(3)-E)(2)(mu(3)-E')(2)] (E, E' = Se, Te 1; S, Te 2; S, Se 4; S, S 7; Se, Se 9) and [Fe3Mo(CO)(11)(mu(3)-E)(mu(3)-E')(mu -E'-E')] (E, E' = S, Te, E'-E' = Te-Te 3; E, E' = S; Se, E'-E' = Se-Se 5; E, E' = S, S, E'-E' = S-Se 6; E, E' = S, S, E'-E' = S-S 8; E, E' = Se, Se, E'-E' = Se-Se 10). The crystal structures of 2, 5, 6 and 8 we re elucidated by X-ray methods. The structure of 2 consists of two dis torted square-pyramidal cores in each of which the alternate corners o f the base are occupied by Fe and chalcogen atoms and a Mo atom occupi es the common apical site. In 5, 6 and 8 a Mo atom occupies the common apical site of a square-pyramidal core and a tetrahedral core. The ba se of the square-pyramidal unit consists of alternate Fe and chalcogen atoms and the tetrahedral base consists of a Fe atom and two chalcoge n atoms.