Perfluoroalkylanilines
The present invention relates to a process for preparing perfluoroalkylanilines and to their use for preparing active ingredients, in particular for agrochemicals.
1. Process for preparing compounds of the formula (I)
in which
R 1 and R 2 are each independently hydrogen, C 1 –C 12 -alkyl, CO(C 1 –C 12 -alkyl), CO(C 5 –C 14 -aryl), CO(C 6 –C 15 -arylalkyl), COO(C 1 –C 12 -alkyl), COO(C 5 –C 14 -aryl) COO(C 6 –C 15 -arylalkyl), COO(C 2 –C 12 -alkenyl) or C 6 –C 15 -arylalkyl, or
NR 1 R 2 as a whole is a cyclic radical having a total of 4 to 16 carbon atoms, or is isocyanate, and
R 3 , R 4 , R 5 and R 6 are each fluorine or C 1 –C 12 -pefluoroalkyl, or two of the R 3 , R 4 , R 5 and R 6 radicals form a cyclic perfluoroalkyl radical having a total of 4 to 20 carbon atoms, and
n is one or two, and
R 7 is C 1 –C 12 -alkyl, C 5 –C 14 -aryl, C 6 –C 15 -arylalkyl, hydroxyl, chlorine, bromine, fluorine, nitro, cyano, free or protected formyl, C 1 –C 12 -haloalkyl, or radicals of the formulae (IIa) to (IIf),
A-B-D-E (IIa)
A-E (IIb)
A-SO 2 -E (IIc)
A-B—SO 2 R 9 (IId)
A-SO 3 W (IIe)
A-COW (IIf)
in which, each independently,
A is absent or is a C 1 –C 8 -alkylene radical and
B is absent or is oxygen, sulphur or NR 8 ,
where
R 8 is hydrogen, C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl or C 5 –C 14 -aryl, and
D is a carbonyl group and
E is R 9 , OR 9 , NHR 10 or N(R 10 ) 2
where
R 9 is C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl, C 1 –C 8 -haloalkyl or C 5 –C 14 -aryl, and
R 10 is in each case independently C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl or C 6 –C 14 -aryl, or N(R 10 ) 2 together is a cyclic amino radical having 4 to 12 carbon atoms and
W is OH, NH 2 or OM where M is an alkali metal ion, half an equivalent of an alkaline earth metal ion, an ammonium ion or an organic ammonium ion, and
m is an integer from 0 to 5−n,
comprising reacting: in step (a):
compounds of the formula (II)
in which
R 1 , R 2 , R 7 and m are each as defined above
with compounds of the formula (III)
R 3 R 4 Hal 1 C—CHal 2 R 5 R 6 (III)
in which
R 3 , R 4 , R 5 and R 6 are each as defined above and
Hal 1 and Hal 2 are each independently chlorine, bromine or iodine,
to give compounds of the formula (IV)
in which
R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , m, n and Hal 1 , are each as defined above and
in a step b),
converting the compounds of the formula (IV) to compounds of the formula (I) by reading with ionic fluoride.
2. Process according to claim 1 , characterized in that
R 1 and R 2 are identically hydrogen or
NR 1 R 2 as a whole is NHCO(C 1 –C 12 -alkyl), NHCO(C 5 –C 14 -aryl) or NHCO(C 6 –C 15 -arylalkyl).
3. Process according to claim 1 , characterized in that
R 3 R 4 FC—CR 5 R 6 as a whole is a secondary C 3 –C 12 -perfluoroalkyl radical.
4. Process according to claim 1 , characterized in that
R 7 is in each case independently C 1 –C 4 -alkyl, chlorine, fluorine, nitro, cyano or C 1 –C 4 -alkoxy.
5. Process according to claim 1 , characterized in that n is 1 and m is 0, 1 or 2.
6. Process according to claim 1 , characterized in that 2-methyl-4-(heptafluoro-2-propyl)aniline is prepared.
7. Process according to claim 1 , characterized in that the compounds of the formula (III) are converted by reacting compounds of the formula (V)
R 3 —CR 4 ═CR 5 —R 6 (V)
with halogen compounds of the formula (VI)
Hal 1 -Hal 2 (VI)
where R 3 , R 4 , R 5 , R 6 , Hal 1 and Hal 2 , are each as defined under formulae (I) and (III).
8. Process according to claim 1 , characterized in that the compounds of the formula (III) used are 1,2-dibromo-1,1,2,3,3,3-hexafluoropropane, 2,3-dibromo-1,1,1,2,3,4,4,4-octafluorobutane, 1,2-dichloro-1,2,3,3,4,4-tetrafluorocyclobutane or 1,2-dibromo-1,2,3,3,4,4,5,5-octafluorocyclopentane.
9. Process according to claim 1 , characterized in that the reaction in step a) is effected in the presence of a reducing agent and/or in the presence of light having a wavelength of 400 nm or less.
10. Process according to claim 9 , characterized in that the reducing agents used are alkali metal dithionites.
11. Process according to claim 1 , characterized in that the reaction is carried out in a multiphase reaction medium which has one aqueous and at least one organic phase.
12. Process according to claim 1 , characterized in that the reaction in step a) is carried out in the presence of a phase transfer catalyst.
13. Process according to claim 1 , characterized in that the reaction temperature in step a) is −10° C. up to the boiling point of the reaction medium under reaction pressure, and the reaction pressure is 0.5 to 100 bar.
14. Process according to claim 1 , characterized in that step a) is carried out in the presence of a base.
15. Process according to claim 1 , wherein compounds of the formula (IV) which bear chlorine or bromine in the ortho-position to the amino group further comprise the steps of reacting the compounds which are unsubstituted in the ortho position in step a) and halogenating to introduce these substituents in the ortho position prior to step b).
16. Process according to claim 1 , characterized in that the ionic fluorides used in step b) are quaternary ammonium fluorides, phosphonium fluorides, or alkali metal fluorides or mixtures thereof or mixtures of phase transfer catalysts and/or halex catalysts with alkali metal fluorides.
17. Process according to claim 1 , characterized in that sodium fluoride, potassium fluoride and caesium fluoride or mixtures thereof are used in step b).
18. Process according to claim 1 , characterized in that step b) is carried out in the presence of organic solvent.
19. Process according to claim 18 , characterized in that maximum water content of the solvent is 1% by weight.
20. Process according to claim 1 , wherein the reaction temperature in step b) is 60° C. up to the boiling temperature of the solvent used at the reaction pressure, characterized in that the maximum reaction temperature is 300° C., with the reaction pressure being 0.5 to 100 bar.
21. Compounds of the formula (IV)
in which
R 1 and R 2 are each independently hydrogen, C 1 –C 12 -alkyl, CO(C 1 –C 12 -alkyl), CO(C 5 –C 14 -aryl), CO(C 6 –C 15 -arylalkyl), COO(C 1 –C 12 -alkyl), COO(C 5 –C 14 -aryl), COO(C 6 –C 15 -arylalkyl), COO(C 2 –C 12 -alkenyl) or C 6 –C 15 -arylalkyl, or
NR 1 R 2 as a whole is a cyclic radical having a total of 4 to 16 carbon atoms, or is isocyanate, and
R 3 , R 4 , R 5 and R 6 are each fluorine or C 1 –C 12 -perfluoroalkyl, or two of the R 3 , R 4 , R 5 and R 6 radicals form a cyclic perfluoroalkyl radical having a total of 4 to 20 carbon atoms, and
n is one or two, and
R 7 is C 1 –C 12 -alkyl, C 5 –C 14 -aryl, C 6 –C 15 -arylalkyl, hydroxyl, chlorine, bromine, fluorine, nitro, cyano, free or protected formyl, C 1 –C 12 -haloalkyl, or radicals of the formulae (IIa) to (IIf),
A-B-D-E (IIa)
A-E (IIb)
A-SO 2 -E (IIc)
A-B—SO 2 R 9 (IId)
A-SO 3 W (IIe)
A-COW (IIf)
in which, each independently,
A is absent or is a C 1 –C 8 -alkylene radical and
B is absent or is oxygen, sulphur or NR 8 ,
where
R 8 is hydrogen, C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl or C 5 –C 14 -aryl, and
D is a carbonyl group and
E is R 9 , OR 9 , NHR 10 or N(R 10 ) 2
where
R 9 is C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl, C 1 –C 8 -haloalkyl or C 5 –C 14 -aryl, and
R 10 is in each case independently C 1 –C 8 -alkyl, C 6 –C 15 -arylalkyl or C 6 –C 14 -aryl, or N(R 10 ) 2 together is a cyclic amino radical having 4 to 12 carbon atoms and
W is OH, NH 2 or OM where M is an alkali metal ion, half an equivalent of an alkaline earth metal ion, an ammonium ion or an organic ammonium ion, and
m is an integer from 0 to 5−n and
Hal 1 is chlorine, bromine or iodine.
22. Compounds according to claim 21 , wherein formula (IV) is selected from the group consisting of 4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)aniline, 2-chloro-4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)aniline, 2-bromo-4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)aniline, 2-fluoro-4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)aniline, 2-methyl-4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)aniline, 2-methyl-4-(2-bromotetrafluoroethyl)aniline, 2-methyl-4-(1-bromo-1,1,2,3,3,3-hexafluoro-2-propyl)acetanilide, 2-methyl-4-(2-bromo-1,1,1,2,3,4,4,4-octafluoro-3-butyl)aniline and 2-methyl-4-(2-bromo-1,2,3,3,4,4,5,5-octafluorocyclo-1-pentyl)aniline.