Oxidation-Resistant Metallocenes. The Synthesis and Properties of Perchloroferrocene and Related Polychlorinated and Fluorinated Ferrocenes
Technical rept. May 1968-May 1969
AIR FORCE MATERIALS LAB WRIGHT-PATTERSON AFB OH
Pagination or Media Count:
Two complete series of novel polychlorinated derivatives of ferrocene, C5H5-nCln2Fe and C5H5-nClnFeC5H5, were prepared and fully characterized. In one series, compounds in which both rings of the metallocene contain the same number from two to five of chlorine atoms were synthesized. Included in this group is decachloroferrocene, the first metallocene derivative completely substituted with electron-withdrawing atoms. The most highly chlorinated members of this series exhibited both a degree of oxidative stability heretofore unobserved in any metallocene and an unpredictedly high thermal stability. The second series of polychlorinated ferrocenes was composed of compounds in which one ring of the metallocene was substituted with from two to five chlorine atoms while the other ring was unsubstituted. This series of derivatives exhibited a decrease in thermal stability with increased chlorine content, indicating that symmetry effects were probably instrumental in providing thermal stability to the first series. As a first step toward the synthesis of fluorine analogs of the polychlorinated ferrocenes, the preparation of fluoroferrocene was accomplished. This compound represents the first known organometallic derivative in which a fluorine atom is directly bonded to a metallocene ring.
- Organic Chemistry