On the efficiency of tetraalkylammonium salts in Heck type reactions

Under appropriate conditions, tetraalkylammonium hydrogensulfate can be just as efficient as tetraalkylammonium chloride or bromide for facilitating Heck-type reactions. Moreover, an appropriate selection of the [Pd / Base / QX] catalyst system can allow this type of reactions to be efficiently realised at will, in a strictly anhydrous medium, in a water-organic solvent mixture or in water alone. Copyright (C) 1996 Elsevier Science Ltd