N-Denitration of N,2,6-trinitroanilines with phase transfer catalysts

A process for the N-denitration of a compound of formula:

• ##STR9## wherein R is C.sub.1 -C.sub.6 alkyl, C.sub.4 -C.sub.6 cycloalkyl, C.sub.1 -C.sub.4 monohaloalkyl or C.sub.1 -C.sub.4 alkoxy(C.sub.2 -C.sub.4)alkyl;
• Y is C.sub.1 -C.sub.4 alkyl, halogen or CF.sub.3 ;
• X is hydrogen, halogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, C.sub.1 -C.sub.4 monohaloalkyl or C.sub.1 -C.sub.4 alkoxy(C.sub.1 -C.sub.4) alkyl;
• comprising:
• reacting the compound with 0.15 to 4.0 molar amount of a phase transfer catalyst, wherein said catalyst is the moiety R.sub.n.sup.1 -Q.sup.+.Z.sup.-, n is an integer of 2,3 or 4;
• wherein each R.sup.1 may be the same or different and is selected from C.sub.1 -C.sub.16 alkyl, C.sub.3 -C.sub.7 cycloalkyl optionally substituted with C.sub.1 -C.sub.3 alkyl, benzyl, substituted benzyl, phenyl, substituted phenyl and the substitutent is HO, halogen, C.sub.1 -C.sub.3 alkyl, C.sub.1 -C.sub.3 alkoxy, Q is N,P,As or S, Z is Cl, Br, I, HSO.sub.4, CH.sub.3 SO.sub.4, H.sub.2 PO.sub.3 or H.sub.2 PO.sub.4, or said catalyst is macrocyclic ethers, macrobicyclic ethers, polyethylene glycols of formula HO--(CH.sub.2 CH.sub.2 O--).sub.m --CH.sub.2 CH.sub.2 OH and m is an integer of 40 to 50, mono and diesters of orthophosphonic acid with ethylene oxide adducts, alkylpyridinium salts or substituted pyrazolium salts;
• in the presence of a water-immiscible solvent of ethylene dichloride, chloroform, monochlorobenzene or carbon tetrachloride;
• and in the presence of an aqueous solution of an alkali metal hydroxide or carbonate or ammonium hydroxide in amounts sufficient to maintain at least pH 7 throughout the reaction;
• and wherein the thus-obtained two-phase reaction mixture is agitated at reflux until the reaction is essentially complete.