Preparation of Isoindolonesby a Lithium-Iodide Exchange-Induced Intra-molecularWurtz-Fittig Reaction of o-IodobenzoylChloride/Imine Adducts

Addition of o-iodobenzoyl chlorides to imines affords N-acyliminium ions, perhaps in equilibrium with α-chlorobenzamides, as adducts. Reaction of the adducts with 1.1 equivalents of phenyllithium at -78 °C followed by warming to ambient temperature induces an intramolecular Wurtz-Fittig coupling to afford 2,3-dihydroisoindolones in excellent yields.