The reaction of Pb(OAc)$\sb2$ or PbCl$\sb2$ with K (HFe(CO)$\sb4$) results in formation of (Et$\sb4$N) $\sb2$ (Pb$\{$Fe$\sb2$(CO)$\sb8\}\{$Fe(CO)$\sb4\}\sb2$) in high yield based on iron. This complex has been structurally characterized and contains a central Pb$\sp{4+}$ atom bound to two (Fe(CO)$\sb4$) $\sp{2-}$ ligands and one (Fe$\sb2$(CO)$\sb8$) $\sp{2-}$ group (Fe-Fe = 2.617(5)A). (Et$\sb4$N) $\sb2$ (M$\{$Fe$\sb2$(CO)$\sb8\}\{$Fe(CO)$\sb4\}\sb2$) reacts with CO and MCl$\sb2$ with excess K (HFe(CO)$\sb4$) to yield products which are formulated as (Et$\sb4$N) $\sb2$ (M$\{$Fe(CO)$\sb4\}\sb2$) on the basis of analytical and spectroscopic data. GeI$\sb2$ is unreactive towards K (HFe(CO)$\sb4$), but when mixed with (Et$\sb4$N) $\sb2$ (Fe$\sb2$(CO)$\sb8$) formation of the novel complex (Et$\sb4$N) $\sb2$ (Fe$\sb3$(CO)$\sb9(\mu\sb3$-CO)$\{\mu\sb3$ - GeFe(CO)$\sb4\}$) occurs. When GeCl$\sb4$ is treated with (Et$\sb4$N) $\sb2$ (Fe$\sb2$(CO)$\sb8$) formation of (Et$\sb4$N) $\sb2$ (Fe$\sb3$(CO)$\sb{11}$) is observed with no evidence of a germanium-containing cluster. These mixed metal anions are oxidized by (Cu(CH$\sb3$CN)$\sb4$) (BF$\sb4$) to form the corresponding neutral spirocyclic M (Fe$\sb2$(CO)$\sb8$) $\sb2$ (M = Sn, Ge, Pb) species. A single crystal X-ray diffraction structure was obtained for the complex Pb (Fe$\sb2$(CO)$\sb8\rbrack\sb2$ (Fe-Fe = 2.90(2)A). Reduction of Ge (Fe$\sb2$(CO)$\sb8\rbrack\sb2$ in benzene or CH$\sb2$Cl$\sb2$ led to the recovery of (Et$\sb4$N) $\sb2$ (Fe$\sb3$(CO)$\sb9(\mu\sb3$-CO)$\{\mu\sb3$-GeFe(CO)$\sb4$). (Et$\sb4$N) $\sb2$ (Pb$\{$Fe$\sb2$(CO)$\sb8\}\{$Fe(CO)$\sb4\}\sb2$) or (Et$\sb4$N) $\sb2$ (Pb$\{$Fe(CO)$\sb4\}\sb2$) are recovered from reduction of Pb (Fe$\sb2$(CO)$\sb8$) $\sb2,$ depending on the solvent used.
Periodic trends were examined by utilizing bismuth as the main group element. The reaction of NaBiO$\sb3$ with K (HFe(CO)$\sb4$) resulted in isolation of (Et$\sb4$N) $\sb3$ (Bi$\{$Fe(CO)$\sb4\}\sb4$) in which a central Bi$\sp{5+}$ atom is tetrahedrally surrounded by four (Fe(CO)$\sb4$) $\sp{2-}$ ligands. This complex decomposes in the presence of gaseous HCl to produce up to 1 mole of H$\sb2$ per mole of cluster via intermediate formation of H$\sb2$Fe(CO)$\sb4.$ Refluxing NaBiO$\sb3$ with Fe(CO)$\sb5$ led to the isolation of (Et$\sb4$N) (BiFe$\sb3$(CO)$\sb9(\mu\sb3$-CO)) which is isoelectronic with (Et$\sb4$N) $\sb2$ (Fe$\sb3$(CO)$\sb9(\mu\sb3$-CO)$\{\mu\sb3$-GeFe(CO)$\sb4\}$) and contains a triangle of iron atoms capped by a bismuth atom on one face and a CO group on the other (Fe-Fe = 2.642(7)A).
When (Et$\sb4$N) (BiFe$\sb3$(CO)$\sb9(\mu\sb3$-CO)) is treated with CO, an extensive rearrangement occurs leading to formation of (Et$\sb4$N) $\sb2$ (Bi$\sb4$Fe$\sb4$(CO)$\sb{13}$) in which there is a central tetrahedron of bismuth atoms attached to iron carbonyl fragments. This complex is the first "Zintl-metal carbonylate" to be reported. (Abstract shortened with permission of author.)
| Identifer | oai:union.ndltd.org:RICE/oai:scholarship.rice.edu:1911/16080 |
| Date | January 1987 |
| Creators | LAGRONE, CRAIG BARTON |
| Source Sets | Rice University |
| Language | English |
| Detected Language | English |
| Type | Thesis, Text |
| Format | application/pdf |
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