Elimination Reactions- Ligand Degradation

In theory, pyrolysis of carbonyl-based heteronuclear cluster compounds should, by analogy with homonuclear carbonyl cluster chemistry, cause elimination of carbon monoxide followed by cluster aggregation. In practice it is difficult to predict the course of these reactions, which can involve simple loss of ligand, cluster aggregation, or degradation, and reactions are often complex and result in low yields. A few... 

No detailed studies on catalyst degradation pathways in ionic liquids have yet been reported. Due to the reaction of [PF6] with water, transformation of P(OR)3 to P(OR)nF3.n has been observed/471 In the case of aqueous biphasic catalysis with TPPTS as ligand, it is known that migration of a phenyl ring and ultimately elimination of sulfonated phenyl derivatives can take place/59,601 However, when suitable (ionic) ligands are employed, the catalyst can remain active for more than 10 cycles and may be stable for more than 14 days under air/4 1... 

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