Date of Award

1-1-1987

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

Abstract

Metal vapor reactor syntheses of 23 $\pi$-areneML$\sb2$ complexes, where M = Fe, Co, or Ni, were attempted. These reactions were used as a synthetic survey to expand the number of complexes available for study. Although the survey has not yet resulted in the isolation of new $\pi$-areneML$\sb2$ complexes, it has resulted in 10 potentially useful synthetic reactions which may eventually lead to several new complexes of this type. In addition, an attempt to synthesize the $\pi$-areneML$\sb2$ complex ($\eta\sp5$-pyrrole)(2,2$\sp\prime$-bipyridine)ion(0) in the synthetic survey lead to the synthesis of the new octahedral complex bis(N-pyrrolyl)bis(2,2$\sp\prime$-bipyridine)ion(II) and the discovery of a new type of metallation reaction at the N-hydrogen of pyrrole and the pyrrole functionality with iron and cobalt.Discovery of the metallation reaction resulted in the synthesis of an iron/pyrrolyl reagent and a cobalt/pyrrolyl reagent. The cobalt/pyrrolyl reagent was synthesized using the metal vapor reactor while the iron/pyrrolyl reagent was synthesized using both the metal vapor reactor and solution techniques. These reagents were used as isolable intermediates in the syntheses of several new and previously reported iron and cobalt complexes. The reagents are believed to be polymeric in nature and enough data was accumulated in the iron system to propose an inorganic iron/pyrrolyl polymeric structure for the iron/pyrrolyl reagent.An interesting new 17 electron cobalt(0) complex, bis(2,2$\sp\prime$-biquinoline)cobalt(0), was synthesized from the cobalt/pyrrolyl reagent and its x-ray structure determined. The complex crystallized in space group P2$\sb1$/c with lattice constants of a = 12.189(2), b = 18.644(3), c = 14.280(2)A, $\beta$ = 107.83(1)$\sp\circ$, and was refined to an R value of 4.6%. The stucture consists of discrete molecules of (C$\sb{18}$H$\sb{12}$N$\sb{2})\sb2$Co with quasi-tetrahedral geometry and an average Co-N complexing distance of 1.952(3)A. Comparisons were made to the structure of the dimeric complex bis(bis(2,2$\sp\prime$-bipyridine)cobalt(0)) by consideration of both steric and electronic effects.The metallation of the N-hydrogen in pyrrole using iron or cobalt was extended to the pyrrole functionality in larger molecules. Both $\alpha, \beta, \gamma, \delta$-tetraphenylporphinatoiron(II) and $\alpha, \beta, \gamma, \delta$-tetraphenylporphinatocobalt(II) were synthesized using the metal vapor cocondensation technique. The addition of $\alpha, \beta, \gamma, \delta$-tetraphenylporphine to an iron/toluene slurry at low temperature resulted in the quantitative conversion of the free porphyrin to $\alpha, \beta, \gamma, \delta$-tetraphenylporphinatoiron(II).

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