A practical and general ipsoiodination of arylboronic acids using N-iodomorpholinium iodide (NIMI) as a novel iodinating agent: mild and regioselective synthesis of aryliodides

A mild and efficient protocol for the ipso-iodination of aryl boronic acids using N-iodomorpholinium iodide (NIMI) generated in situ from morpholine and molecular iodine as a novel iodinating agent has been developed. The addition of a catalytic amount of copper iodide found to promote rate enhancement of the iodination reaction and dramatic increase in the yield depending upon the nature of the boronic acid was observed. The mechanistic study revealed that depending upon the nature of the substrate, either the classical ipsosubstitution or copper catalysed iododeborylation pathway overall dominates the present iodination reaction. The features such as mild reaction conditions, operational simplicity, high to excellent yields, excellent functional group compatibility and low catalyst loading make this method potentially useful in organic synthesis.