Enantioselective conjugate addition of stabilized arylzinc iodide to enones: an improved protocol of the Hayashi reaction

Stabilised arylzinc iodide, prepared by direct insertion of zinc into aryl iodides, were used as nucleophiles in the Hayashi Rh-catalysed enantioselective conjugate addition to enones. The reaction conditions were optimized in the addition of phenylzinc iodide to 2-cyclohexen-1-one, obtaining good yields and 99% ee of the addition product. The general applicability of the protocol was checked using different arylzinc iodides and enones. Organometallic reagents endowed with both halogen and electrophilic groups were also successfully used.