Iron carbonyl complexes of Schiff bases and azo compounds

Bagga, Madan M (1965) Iron carbonyl complexes of Schiff bases and azo compounds. PhD thesis, University of Glasgow.

Abstract

Schiff bases of aromatic aldehyes and ketones react with diiron enneacarbonyl at room temperature giving complexes with the molecular formula (base)Fe2(CO). Azines and hydrazones afford analogous complexes. Schiff bases give low yields of the same complexes when irradiated with iron penta-carbonyl, whereas azines do not react under these conditions. Azobenzene reacts with iron pentocarbonyl when irradiated to give a metal carbonyl complex corresponding to the formula (azobenzone)Fe2(CO)6, which in fact is derivative of ortho-semide; in addition to this type, substituted azobenzenes also give products of the type (azobenzene)2Fe(CO)2. Reaction of azotoluene with diiron enneacarbonyl at room temperature gives yet another type of complex in extremely low yield. The mass spectral and chemical degradation and probable structures of these complexes are discussed. Diphenyldiazomethane reacts with iron pentacarbonyl when irradiated giving two different types of complexes; its reaction with triiron dodecacarbonyl gives predominantly one of these 4.4'-Ditololyldiazomethane affords similar complexes, but phenyldiazomethane and phenylbenzoyldiazomethane give only unstable products in low yields. The most notable feature of this work is that diphenylketene, an irradiation product of phenylbenzoyldiazomethane reacts smoothly with iron penta-carbonyl when irradiated to give complex in fairly high yield. Based on analytical, mass spectral and chemical degradation work, possible structures are proposed for these complexes. Diphenyldiazomethane does not react to give any complexes when irradiated with nickel tetracarbonyl, methylcyclopentadienyl-manganese tricarbonyl and chromium hexacarbonyl. Tetramethyl-2-tetrazene reacts with iron pentacarbonyl when irradiated giving a complex in low yield; its reaction with dirron enneacarbonyl at room temperature gives an unstable liquid complex. Diazofluorine affords two complexes in very low yields, on treatment with diiron enneacarbonyl and different complex when irradiated with iron pentacarbonyl; the latter compound shows both bridging and terminal metal carbonyl absorption in the infrared spectrum. Diazocyclopentadiene gives an unstable liquid complex when irradiated with iron pentacarbonyl. No complexes are formed from ethyl azodicarboxylate and iron pentacarbonyl or diiron enneacarbonyl. In view of the instability and low yields of these complexes, it has not been possible to carry out any chemical work on them. Attempts to form complexes from fluorine, fluorenone or tetraphenylethylene and iron pentacarbonyl by irridation are not successful. Some reactions between the complex obtained from acetylene and the iron tetracarbonyl anion and the following reagents are carried out in order to study the chemistry of this rather interesting compound. Its reaction with dichlorophenylphosphine does not give any phosphole. When irradiated, it yields an unstable complex. In order to see whether it is possible to replace one or more carbonyl groups by diphenylcarbene it is irradiated with diphenyldiazomethane. No such reaction occurs; instead two nitrogen containing complexes are obtained. Its reaction with phenylacetylene gives a metal complex in very low yield. Although the study of these compounds is incomplete some data are presented on them.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: P L Pauson
• Keywords: Organic chemistry, Inorganic chemistry
• Date of Award: 1965
• Depositing User: Enlighten Team
• Unique ID: glathesis:1965-73808
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 14 Jun 2019 08:56
• Last Modified: 14 Jun 2019 08:56
• URI: https://theses.gla.ac.uk/id/eprint/73808