The invention concerns novel catalysts for aromatic nucleophilic
substitution. Said catalysts are compounds of the general formula (I),
wherein: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, and R.sub.6,
identical or different, are selected among hydrocarbon radicals; the
Pn's, advantageously the same, are selected among metalloid elements of
column V of a period higher than nitrogen; Z is a metalloid element of
column V, advantageously distinct from Pn; preferably a nitrogen (N, P,
As, Sb). The invention is applicable to organic synthesis ##STR00001##