A tandem cross-coupling reaction of ketones with aldehydes has been achieved using barium hydride or isopropoxide as a promoter, in which barium enolates are generated in situ and then three successive reactions (aldol reaction-β-elimination-Michael addition) follow; this one-pot process is effective for obtaining symmetrical 1,5-diketones in good yields.
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.