Preparation, properties and coordination of new conjugated ferrocenyl-based ligands with an end-capped nitrile

New ferrocenyl-nitrile conjugated ligands have been obtained by several routes in which we combined Wittig and Horner–Emmons–Wadsworth (HEW) reactions, being the latter the one that shows better results both in yield and selectivity for the E isomers. The coordination capabilities of these new ligands have been proved using different metal carbonyls and the electronic spectra of the compounds have been studied, showing a clear dependence on the length of the conjugated chain and in the nature of the coordinated metal carbonyl fragment.