Tetraruthenium carbonyl complexes containing germyl and stannyl ligands from the reactions of Ru 4 (CO) 13 (m-H) 2 with HGePh 3 and HSnPh 3 Richard D. Adams * , Yuwei Kan, Vitaly Rassolov * , Qiang Zhang Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA article info Article history: Received 16 July 2012 Received in revised form 10 August 2012 Accepted 17 August 2012 Keywords: Ruthenium Germanium Tin RueGe bonding DFT UVevis spectra abstract The compounds Ru 4 (CO) 12 (GePh 3 ) 2 (m-H) 4 , 1 and Ru 4 (CO) 12 (SnPh 3 ) 2 (m-H) 4 , 2 were obtained from the reactions of Ru 4 (CO) 13 (m-H) 2 with HGePh 3 and HSnPh 3 , respectively. Both compounds contain a nearly planar butterfly structure for the four metal atoms with two GePh 3 /SnPh 3 ligands and four bridging hydride ligands around the periphery of the cluster. When heated, 1 and 2 were converted into the complexes Ru 4 (CO) 12 (m 4 -EPh) 2 , 3,E ¼ Ge, and 4,E ¼ Sn, by cleavage of two phenyl groups from each of the GePh 3 ligands. Compounds 3 and 4 contain square planar arrangements of the four ruthenium atoms with quadruply bridging germylyne and stannylyne ligands on opposite sides of the square plane. The bonding and electronic transitions of 3 were analyzed by DFT computational analyses. Ó 2012 Elsevier B.V. All rights reserved. 1. Introduction Studies have shown that mixed metal cluster complexes can serve as precursors to superior bi- and multi-metallic nanoscale heterogeneous catalysts [1]. Germanium [2] and tin [1a,1b,3] are well known to serve as excellent modifiers for heterogeneous transition metal catalysts. We have been investigating the synthesis and structures of metal carbonyl cluster complexes containing phenylgermanium [4] and phenyltin [5] ligands for use as precur- sors to new nanoscale particles [5a] and heterogeneous catalysts when placed on supports [3q]. Polynuclear transition metal carbonyl cluster complexes con- taining terminally-coordinated EPh 3 ligands A,E ¼ Ge or Sn, bridging EPh 2 ligands, B, triply-bridging EPh ligands, C and quadruply-bridging ligands EPh, D have been obtained from reac- tions of a variety of transition metal carbonyl cluster complexes with HGePh 3 , Eqs. (1)e(4) [4a,6e8]. When using HEPh 3 as a reagent, it is not uncommon to obtain metal carbonyl products containing terminally coordinated EPh 3 ligands [9]. For example, the reaction of Ru 3 (CO) 12 with HEPh 3 yields the product Ru 3 (CO) 9 (EPh 3 ) 3 (m-H) 3 , among many others, which contains three EPh 3 ligands [4c,]. When heated, Ru 3 (CO) 9 (EPh 3 ) 3 (m-H) 3 eliminates one phenyl ring from each EPh 3 ligand and the three hydride ligands to form trisegermylene and trisestannylene complex Ru 3 (CO) 9 (m-EPh 2 ) 3 , Eq. (5) [4c,5b]. We recently obtained the IrRu 3 complex IrRu 3 (CO) 11 (GePh 3 ) 3 (m-H) 4 from the reaction of IrRu 3 (CO) 13 (m-H) with HGePh 3 . When heated, IrRu 3 (CO) 11 (GePh 3 ) 3 (m-H) 4 was converted to the compounds IrRu 3 (CO) 10 (m-h 2 -C 6 H 5 )(m 4 -GePh) 2 and IrRu 3 (CO) 9 (m-h 2 -C 6 H 5 ) (m 4 -GePh) 2 (m-GePh 2 ), Eq. (6) [9]. These products contain quadruply- bridging germylyne ligands formed by cleavage of the phenyl groups from the GePh 3 ligands. Each product also contains one of the cleaved phenyl rings that serves as a bridging m-h 2 -C 6 H 5 ligand. Recently, it has been shown by a computational analysis that the a-cleavage of a phenyl group from a GePh 3 ligand in the transformation of the triiridium complex Ir 3 (CO) 6 (m-CO) (m-GePh 2 ) 2 (GePh 3 ) 3 into the complex Ir 3 (CO) 6 (h 1 -Ph)(m-GePh 2 ) 3 (GePh 3 ) 2 , Eq. (7), occurs at a single iridium atom [10]. We have recently obtained a series of tetraruthenium complexes containing both edge-bridging EPh 2 ligands and quadruply bridging EPh ligands, E ¼ Ge or Sn, from the reactions of Ru 4 (CO) 12 (m-H) 4 with HGePh 3 and HSnPh 3 , Eq. (4) [3q,4a]. No intermediates containing GePh 3 or SnPh 3 ligands were observed in these reactions. A number of cobalt complexes containing quadruply bridging germylyne ligands have been prepared by using alkylgermanes [11]. We have now investigated the reactions of Ru 4 (CO) 13 (m-H) 2 with HGePh 3 and HSnPh 3 and have obtained the new tetrahy- dridotetraruthenium complexes Ru 4 (CO) 12 (EPh 3 ) 2 (m-H) 4 , 1 ,E ¼ Ge, * Corresponding authors. E-mail address: Adamsrd@mailbox.sc.edu (R.D. Adams). Contents lists available at SciVerse ScienceDirect Journal of Organometallic Chemistry journal homepage: www.elsevier.com/locate/jorganchem 0022-328X/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jorganchem.2012.08.021 Journal of Organometallic Chemistry xxx (2012) 1e12 Please cite this article in press as: R.D. Adams, et al., Journal of Organometallic Chemistry (2012), http://dx.doi.org/10.1016/ j.jorganchem.2012.08.021