Metallocene to metallocene conversion. Synthesis of an oxazoline-substituted pentamethyliridocenium cation from a ferrocenyloxazoline

Abstract

Reaction of (S)-2-ferrocenyl-4-(1-methylethyl)oxazoline with [Cp*IrCl₂]₂ in benzonitrile with KPF₆ and NaOH gave (η⁵-(S)-2-(4-(1-methylethyl))oxazolinylcyclopentadienyl)(η⁵-pentamethylcyclopentadienyl)iridium(III) hexafluorophosphate (68%). This transformation of an iron-based into an iridium-based metallocene proceeds via the rearrangement, with loss of cyclopentadienyliron, of an intermediate cationic ferrocenyliridacycle.