Synthesis and X-ray analysis of the tetrahydrido-dianion [H₄Os₁₀(CO)₂₄]^2–, the first non-carbido decaosmium cluster

Abstract

The non-carbido decaosmium cluster dianion [H40~,0(C0)24]2-(1 ) has been prepared in low yield by heating several trinuclear osmium clusters in isobutyl alcohol; X-ray analysis of the [ (Ph,P),N] + salt shows that the tetrahydrido-dianion (1) is very similar in structure to the carbido-dianion [OS,~C(CO)~~]~- (2) indicating that the four hydrido-ligands in (1) may possibly be interstitial in the solid state.The tetrahydrido-dianion [H40~lo(C0)24]2-(I), which has been obtained in low yield by heating Os,(CO),,, Os,(CO),,-(OEt),,' HOs,(CO),,CI, or Os,(CO),,/sodium benzoate in isobutyl alcohol is the first example of a new type of decaosmium cluster which does not contain a central carbidoatom. The first Oslo cluster species to be isolated was the dianion [OS~~C(CO),~]~-(2) in which, for the first time, a carbon atom was located in an octahedral Os, cavity.2 Since then several derivatives of this species have been isolated3p4 and until now all have been found to contain the same basic carbido-centred octahedral Os, unit.We recently reported that a range of high nuclearity cluster compounds is obtained when Os,(CO),, is heated in KOH/ Bu'OH.~ We now find that, when the reaction is carried out in BuiOH under reflux (108 "C) in the absence of base,? ? At 130 "C in 2-methylbutan-1-01 or on prolonged reflux in Bu'OH the carbido-dianion is formed showing that the reaction may be very sensitive to small changes in reaction conditions.

The chemistry of hydridocarbonylferrates revisited: syntheses and structures of the new [H2Fe4(CO)12]2− and [HFe5(CO)14]3− anions, and the [Fe(DMF)4][Fe4(CO)12(μ5-η2-CO)(μ-H)]2 adduct containing an unprecedented isocarbonyl

“…6 It must be remarked that the heavier Ru and Os congeners display a much richer cluster chemistry which includes species with nuclearity up to 20, e.g. [H 2 -n Os 5 (CO) 15 ] n-(n = 0-2), 7 Os 5 (CO) 16 , 8 Os 6 (CO) 18 , 9 Os 7 (CO) 21 , 10 Os 8 (CO) 23 , 11 [H 4 Os 10 (CO) 24 ] 2-, 12 [Os 17 (CO) 36 ] 2-, 13 and [Os 20 (CO) 40 ] 2-. 14 As a result of our ongoing interest in the chemistry of carbonylferrates and hydridocarbonylferrates, we herein report on the synthesis and X-ray structure of the [H 2 Fe 4 (CO) di-hydride di-anion, quantitatively obtained by protonation of [HFe 4 (CO) 12 ] 3in DMSO, as well as the serendipitous isolation and structural characterization of the new pentanuclear [HFe 5 (CO) 14 ] 3mono-hydride tri-anion.…”

Tetracarbalane structures: nido polyhedra and non-spherical deltahedra

“…10 and Table 3). 44 The next C 4 Al 6 Me 10 structure Al6C4-2, lying 4.3 kcal mol −1 in energy above Al6C4-1, is a C s structure based on the 10-vertex isocloso deltahedron, which has only three degree 4 vertices in addition to six degree 5 vertices and a unique Fig. Structure Al6C4-1 is a very symmetrical D 2h tetracapped octahedron in which two pairs of edge-sharing triangular faces of a central Al 6 octahedron are capped with C 2 units having relatively long C-C bonding distances of 1.577 Å.…”

Reactions of some decaosmium clusters with electrophilic and nucleophilic reagents: X-ray structure analyses of [N(PPh3)2][Os10C(CO)24(µ-I)], [Os10C(CO)24(µ-I)2], [N(PPh3)2]2[Os10C(CO)22(NO)I], [Os10C(CO)23{P(OMe)3}(µ-I)2] and of two isomers of [Os10C(CO)21{P(OMe)3}4]

“…techniques. From the complex product mixture six complexes (5)-- (10) were separated in sufficient yields to be characterised by i.r. spectroscopy in the v(C0) region (Table 2), however no e.i.m.s.…”

“…A combination of spectroscopic and analytical data together with an X-ray structure determination established that (5) is the neutral compound [Os, 0C(C0)23{ P(OMe),}(p-I),], but the other products (7)-- (10) have not been fully characterised (see Table 2). The structure of (5) is shown in Figure 6 and selected bond lengths and angles are given in Table 3 for comparison longer than that of 2.818(2) !i in (6), and considerably longer 4) Os(7)-C(39)-os (9) 74.1(7) OS(7)-c( 39)-O(39)…”