The structures, physical properties, and reaction chemistry of molybdenum (V) and tungsten (V) porphyrin complexes are investigated. The four, five-coordinate nitrido molybdenum (V) and tungsten (V) complexes MoN(TMP), MoN(TPP), MoN(TTP), and WN(TPP) have been synthesized and characterized by mass, ESR, IR, and UV-Visible spectroscopic methods. Furthermore, one of the nitrido complexes MoN(TMP) and imido derivative (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$ have been characterized by single-crystal X-ray diffraction techniques. MoN(TMP) has a square pyramidal structure in the solid state, with the Mo-nitrido bond length of 1.630 (4) A and nitrogen atom at the apical position. The terminal nitrido ligand is triply bonded to the metal. Nitrido complexes MoN(TMP) and MoN(TPP) form 1:1 adducts with Lewis acid, methylates at nitrogen atom upon reaction with methyl iodide, displaces one CO ligand from Mo(CO)$\sb6$, and react with HCl gas to produce (porph)MoN--BF$\sb3$, (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$, (TPP)MoN--Mo(CO)$\sb5$, and ((porph)MoN--H) $\sp+$Cl$\sp-$, respectively. Also, nitrido complexes react with tertiary alkyl phosphines to form phosphineiminato complexes. (Mo(NMe)(TPP)(H$\sb2$O)) $\sp+$(I$\sb3$)$\sp-$ has a distorted octahedral structure in the solid state, with the Mo-imido bond length of 1.689 (6) A and the Mo-N-CH$\sb3$ angle of 175.34 (64)$\sp\circ$. Thus, the imido ligand in this compound acts as a four $\pi$-electron donor. / Quadruply bonded (W(TPP)) $\sb2$ and its reaction derivative WN(TPP) also have been synthesized. Diamagnetic tungsten dimer (W(TPP)) $\sb2$ shows the very similar spectroscopic patterns to those of (Mo(TPP)) $\sb2$. Temperature dependent $\sp1$H NMR spectra of this complex show two NMR distinct $\beta$-pyrrole protons at $-$48$\sp\circ$C due to the rotation about $\delta$ component tungsten-tungsten quadruple bond. The activation barrier was estimated 11.3 kcal/mole from the NMR line shape analysis. (W(TPP)) $\sb2$ reacts with p-tolyl azide to produce paramagnetic WN(TPP). / Source: Dissertation Abstracts International, Volume: 52-03, Section: B, page: 1425. / Major Professor: Virgil L. Goedken. / Thesis (Ph.D.)--The Florida State University, 1991.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_76375 |
| Contributors | Kim, Juchang., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 168 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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