a) nucleophiles selected from the group alcohols, thioles, amines, metallised hydrocarbons, CH-acidic compounds and metal cyanides, or of b) carbon monoxide mixed with water, alcohols, ammonia, primary or secondary amines, to organic compounds selected from the group of leaving-group-containing aromatics, hetero-aromatics with a C-bonded leaving group, aromatic or hetero-aromatic methyl compounds with a leaving group bonded to the methyl group, ethylenically unsaturated organic compounds with a C-bonded leaving group, or organic allyl compounds with a leaving group in allyl position, or c) vinyl compounds with leaving-group-containing aromatics, whilst cleaving the leaving group in the presence of Pd complexes with monophospholine ligands as the catalyst, whereby variants b) and c) are carried out in the presence of an inorganic base or organic nitrogen base, the process being characterised in that the Pd complex contains secondary monophosphines with aliphatic, branched or cyclic substituents as ligands.