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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A crystallographic investigation comparing five 1-aryl-substituted tricarbonyl[(1–5-?)-cyclohexadienyl]iron(1+) salts demonstrates that introducing additional electron density on the aromatic ring increases p overlap between the arene and the cyclohexadienyl ligand, thus flattening the structures sufficiently to make available a conformation in which nucleophiles can approach the site of substitution, despite the steric blockade of o-benzyl substituents

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Aryllithium reagents generated from protected 6‐bromoguaiacol and 2‐bromo‐4,5‐dimethoxybenzyl alcohol derivatives were used to prepare ortho‐substituted (1‐arylcyclohexadienyl)iron(1+) electrophiles. These were treated with Na+[Me3SiCH2CH2O2CCHCN]– to build aryl‐substituted quaternary centres in new examples of 1,1 iterative {[η4] → [η5]+ → [η4] → [η5]+ → [η4]} reaction sequences, which make use of the electrophilicity of the metal complex in two key carbon–carbon bond‐formation steps. MOM protection of the guaiacol was better than SEM for access to the lycoramine skeleton, and TBDPS was best for maritidine. Decomplexation, hydrolysis, and cyclisation completed formal total syntheses of the Amaryllidaceae alkaloids (±)‐lycoramine and (±)‐marididine, establishing the compatibility of the organoiron method with the presence of ortho substituents on the aryl group, and nucleophile addition ipso to the substituted arene.

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