Davies-Green-Mingos rules ligands

The Davies-Green-Mingos rule predicts that the attack at butadiene ligand should occur at the terminal carbon, as is consistent with the OAc attack at the... 

Figure 11.4. Order of reactivity of ir-ligands according to the Davies-Green-Mingos rules.

Green-Davies-MIngos Rules It is not unusual for a single complex to have several polyene or polyenyl ligands, in which case we often see selective attack at one site of one ligand only. Green, Davies and Mingos noticed certain patterns in these reactions and from them devised a set of rules that usually allow us to predict the site of addition. 

The nucleophilic attack on a polyhapto ligand occurs with a decrease of the hapticity by one unit in the reaction product. In addition, three rules established by Davies, Mingos and Green appear, when the reaction is under charge control, to determine the regioselectivity of the attack, if several hydrocarbon ligands are present in the same complex or if several possible sites are available for the nucleophilic attack ... 

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