Triosmium clusters containing bridging sulphur, hydrido, and diphosphine ligands: A study of hydride site preferences and mobility

Hexa- and triosmium carbonyl clusters bearing bridging dppm and capping sulfido ligands

“…Electronically, the cluster [Os 6 (CO) 17 (l 4 -S) 2 ], also contains two electrons in excess of the requirements of the 18-electron rule and it was proposed that these electrons also occupy a low-lying antibonding orbital and also exhibits elongated metal-metal bonds [7]. The Os-S bond distances in 4 lie within the range {2.316(6)-2.410(5) Å } and are comparable to those observed for other capping sulfido bridges (2.35-2.45 Å ) [13][14][15][16]. The details of the nature of the delocalized bonding in cluster 4 remain to be established.…”

“…In this paper we report the synthesis of [Os 3 (l 3 -S) 2 (CO) 6 (Me 3 N)(l-dppm)] (2) and [Os 6 (CO) 12 (l 3 -S) 4 (l-dppm) 2 ] (3) by the Me 3 NO initiated self condensation reaction of 1. We also describe the synthesis of the hexanuclear complex 14 (l 3 -S) 2 (l-dppm)] (4) from the reaction of 1 with [Os 3 (CO) 10 (MeCN) 2 ]. These complexes permit the direct comparison of the structures of [Os 6 (CO) 12 (l 3 -Se) 4 (ldppm) 2 ] and [Os 6 (CO) 14 (l 3 -S) 2 (l-dppm)] with those of the unsubstituted complexes [Os 6 (CO) 16 (l 3 -S) 4 ] and [Os 6 (CO) 17 (l 4 -S) 2 ].…”

“…We also describe the synthesis of the hexanuclear complex 14 (l 3 -S) 2 (l-dppm)] (4) from the reaction of 1 with [Os 3 (CO) 10 (MeCN) 2 ]. These complexes permit the direct comparison of the structures of [Os 6 (CO) 12 (l 3 -Se) 4 (ldppm) 2 ] and [Os 6 (CO) 14 (l 3 -S) 2 (l-dppm)] with those of the unsubstituted complexes [Os 6 (CO) 16 (l 3 -S) 4 ] and [Os 6 (CO) 17 (l 4 -S) 2 ]. To further explore the reactivity of [Os 3 (CO) 7 (l 3 -S) 2 (l-dppm)] (1) and [Os 3 (l 3 -S) 2 (CO) 6 -(Me 3 N)(l-dppm) (2) we have examined their interactions with CO, PPh 3 and P(OMe) 3 and the results are also described in the present paper.…”

“…For example, Adams et al [4] reported the synthesis of the mixed-metal cluster [Os 3 (CO) 9 (l 4 -S)(l 3 -S){W(CO) 5 }] from the photo-induced reaction of [Os 3 (CO) 9 (l 3 -S) 2 ] with W(CO) 6 is coordinated through a l 4 -S atom. They also reported that when irradiated in presence of [W(CO) 5 (PMe 2 Ph)], the compound [Os 3 (CO) 9 (l 3 -S) 2 ] yields four mixedmetal clusters [Os 3 W(CO) 12 (l 3 -S) 2 (PMe 2 Ph)], [Os 3 W(CO) 12 -(l 3 -S) 2 (PMe 2 Ph) 2 ], [Os 3 W(CO) 11 (l 3 -S) 2 (PMe 2 Ph) 2 ] and [Os 3 W 2 (CO) 14 (l 4 -S)(l 3 -S)(PMe 2 Ph) 2 ] [5]. The cluster [Os 3 (CO) 9 (l 3 -S) 2 ] was also found to react with Os(CO) 5 under UV irradiation to form [Os 4 (CO) 13 (l 3 -S) 2 ].…”

“…Molecular structure of[Os 6 (CO) 14 (l 3 -S) 2 (l-dppm)](4)showing the crystallographic labeling scheme. Thermal ellipsoids are at the 50% probability level.…”