ABSTRACT
Solventless reactions of substituted cyclopentadienyl metal carbonyls of iron and ruthenium
with electron donor ligands have been carried out.
The reactions between CpFe(CO)2I and a range of phosphine ligands occurred in melt phase
and yielded two typical compounds : salt product, [CpFe(CO)2PR3]I, and non-salt product,
CpFe(CO)PR3I with the salt product being predominant. The complex [CpFe(CO)2]2 was
used to catalyze these reactions. The progress of the reactions was followed by 1H NMR
spectroscopy. The characterization of products correlates well with the products obtained
when working in solution medium.
The presence of a Me substituent on the Cp ring was found to favour the salt product
formation but generally led to lower rates of reaction.
Solventless reactions between RCpRu(CO)2I (R = H, Me) and solid phosphine ligands were
also carried out. It has been observed that the ruthenium complexes were less reactive
compared with their iron analogues but led to the same types of products namely salt and
non-salt.
The phosphite ligands were found to be less reactive than their phosphine analogues. In fact,
the solventless reactions between RCpM(CO)2I (R = H, Me; M = Fe, Ru) were very slow
even in the presence of [CpFe(CO)2]2 as a catalyst. However, when Me3NO.2H2O was added
to the reaction mixture in solventless conditions, the non-salt product was obtained in a short
period of time at 80oC.
A range of cyclopentadienyl based metal complexes e.g [CpMo(CO)3]2, [MeCpRu(CO)2]2
etc. and palladium based compounds such as PdO, Pd/CaCO3 5% etc. were found to be good
catalysts for the solventless reactions between CpFe(CO)2I and PPh3. Solventless migratory-insertion reactions have been successfully conducted between
CpFe(CO)2CH3 and a range of solid phosphine ligands. Only the acetyl products,
CpFe(CO)[PR3]COCH3 were obtained.
SO2 insertion into RCpFe(CO)2R’ (R = H, CH3; R’ = CH3, CH2Ph) occurred quite easily at
room temperature. However, when R was a carboxylic acid group, CO2H, no reaction took
place. CO insertion into the same systems did not happen in solventless conditions.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:wits/oai:wiredspace.wits.ac.za:10539/4560 |
| Date | 06 March 2008 |
| Creators | Munyaneza, Apollinaire |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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