Catalyst for nucleophilic aromatic substitutions

A catalyst suitable for nucleophilic substitution, consisting essentially of:

• a mixture of a component a) and a component b), wherein component a) is at least one quaternary ammonium compound of the formula (1) ##STR3## in which R.sup.1, R.sup.2 and R.sup.3 are identical or different and are a linear or branched alkoxypolyoxyalkyl radical of the formula --(C.sub.m H.sub.2m O).sub.p R.sup.5, in which R.sup.5 is hydrogen or a linear or branched alkyl radical having from 1 to 16 carbon atoms, m is an integer from 1 to 10 and p is a number from 1 to 15;
• a linear or branched alkyl radical having from 1 to 30 carbon atoms;
• or an unsubstituted phenyl or naphthyl radical;
• or a substituted phenyl or naphthyl radical, with the substituents being halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, nitro or cyano;
• R.sup.4 is a linear or branched alkoxypolyoxyalkyl radical of the formula --(C.sub.m H.sub.2m O).sub.p R.sup.5, wherein R.sup.5, m, and p are as defined above, and;
• X is an inorganic anion;
• and
• component b) is at least one quaternary ammonium salt or at least one phosphonium salt of the formula (2) ##STR4## in which R.sup.6, R.sup.7, R.sup.8, and R.sup.9 are identical or different and are a linear or branched alkyl radical having 1 to 22 carbon atoms;
• or an unsubstituted or substituted aryl radical or a C.sub.1 -C.sub.4 -alkyl-aryl radical, with aryl being phenyl or napthyl, and the said substituents are halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy, nitro or cyano;
• and
• Y is N or P;
• or
• the mixture consists essentially of component a) as defined above, and a component c), which is at least one polyether of the formula (3)
• R.sup.10 --(O--C.sub.x H.sub.2x).sub.r --OR.sup.11 ( 3),
• in which
• R.sup.10 and R.sup.11 are identical or different and are hydrogen or a linear or branched alkyl radical having from 1 to 16 carbon atoms,
• x is an integer from 2 to 6 and
• r is a number from 0 to 20;
• or
• the mixture consists essentially of component a) as defined above, and a crown ether;
• or
• the mixture consists essentially of component a) as defined above, component b) as defined above, and component c) as defined above.