Nickel-Catalysed 1,4-Addition of Aryl Groups to Enones Using Aryldialkylaluminum Compounds

The transmetallation of arylmagnesium halides or aryllithium with Me2AlCl results in the formation of aryldimethylaluminum compounds. These arylaluminum compounds are useful reagents for conjugate additions to enones in the presence of Ni(acac)2 as a catalyst. 3-Aryl ketones are obtained in good yields in these catalytic reactions. Starting from the 3-oxo-Δ1,4-steroids this method gives access to 1α-arylsteroids.