South African Journal of Chemistry
On-line version ISSN 1996-840X
Print version ISSN 0379-4350
MUNYANEZA, Apollinaire; BALA, Muhammad D. and COVILLE, Neil J.. Solventless substitution reaction of solid phosphine ligands with Ru(C5H4R)(CO)2I (R = H, Me). S.Afr.j.chem. (Online) [online]. 2009, vol.62, pp.14-19. ISSN 1996-840X.
The solventless reaction between Ru(C5H4R)(CO)2I (R = H, Me) and solid phosphine ligands [PPh3/ P(p-MeOC6H4)3, P(m-MeC6H4)3,P(p-FC6H4)3,P(p-ClC6H4)3] was undertaken at various temperatures with all the reactions occurring in the melt phase. The reaction rates and type of products isolated are dependent on the electronic properties of the Cp-substituent and the para-substituent on the phosphine ligands. For the C5H4R moiety, when R = H the ligand substitution product Ru(C5H5)(CO)(PR3) I was obtained, and the ligand addition product [Ru(C5H4Me)(CO)2(PR3)]I was predominantly obtained when R = Me. The reaction rates are enhanced by para-substituted electron-donating phosphines. These results are similar to those obtained from studies utilizing benzene and xylene as solvents. The products have been characterized by FTIR and NMR spectroscopy and by MS. The complex Fe2(C5H5)2(CO)4 was found to act as a catalyst in all the melt reactions.
Keywords : Solvent-free; ruthenium; cyclopentadienyl complexes; phosphines.