文摘
The addition of phosphonate stabilized carbon nucleophiles to acyclic (pentadienyl)iron(1+) cations proceeds predominantly at an internal carbon to afford (pentenediyl)iron complexes. Those complexes bearing an electron withdrawing group at the σ-bound carbon (i.e., <strong class="boldFont">13strong>/<strong class="boldFont">14strong>) are stable and isolable, while complexes which do not contain an electron withdrawing group at the σ-bound carbon undergo CO insertion, reductive elimination and conjugation of the double bond to afford cyclohexenone products (<strong class="boldFont">21strong>/<strong class="boldFont">22strong>). Deprotonation of the phosphonate <strong class="boldFont">13strong>/<strong class="boldFont">14strong> or <strong class="boldFont">21strong> and reaction with paraformaldehyde affords the olefinated products. This methodology was utilized to prepare oxygenated carvone metabolites (±)-<strong class="boldFont">25strong> and (±)-<strong class="boldFont">26strong>.