A series of aryl-substituted cyclohexadienyliron complexes have been prepared by a general procedure that determines regioselectivity by correctly positioning leaving groups in the precursor complexes. The aryl groups at 1-C or 2-C have been shown to be omega directing by the study of reactions with a representative range of nucleophiles, and these regioselectivity properties have been related to the spectroscopic properties of the cationic cyclohexadienyliron complexes. A high level of electron-donating substituents on the arene, or switching between the [Fe(CO)3] and [Fe(CO)2PPh3] series, reduces the minor ipso pathway, improving regiocontrol. Placing opposed directing groups in the arylcyclohexadienyliron complexes reverts reactivity to the ipso pathway with stabilised enolate nucleophiles, and when the additional directing group reinforces the effect of the aryl group, the ipso pathway is stopped.

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Disubstituted (cyclohexadienyl)iron(1+) complex 2b is prepared by an improved route that starts from 1,2‐dimethoxycyclohexa‐1,4‐diene 3. In five steps, the synthesis of 2b is achieved by complexation with Fe(CO)5, hydride abstraction, hydrolysis, addition of EtO2CCH2ZrBr, and reaction with HBF4. In the presence of dimethyl sulfide, the reaction of 2b with 2‐[CH2N(CH2CH=CH2)2]‐functionalized diarylcuprate reagent 7 gave the 5α‐arylcyclohexadiene complex 1b in 88 % yield. A DFT study compared diarylzinc and diarylcuprate reagents containing chelating CH2NMe2 substituents.