A tandem cross-coupling reaction of aryl methyl ketones with aromatic aldehydes has been accomplished employing barium isopropoxide as a catalyst, in which barium enolates are generated and then three consecutive reactions (aldol reaction/beta-elimination/conjugate addition) occur; this one- pot procedure is a convenient method to obtain symmetrical 1,5-diketones in good yields. In some cases, addition of iso- propanol is effective in improving the chemical yield. (c) 2007 Elsevier Ltd. All rights reserved.