DD249382A3 - METHOD FOR PRODUCING PIPERAZINIUM SALTS - Google Patents

Abstract

The invention relates to a process for the preparation of piperazinium salts by reaction of aromatic amines with alkyl halides or directly their ammonium salts at higher temperatures. The process of the invention is based on the fact that aromatic amines are used for the preparation of the piperazinium salts, which rearrange in a simple manner and in good yield. Both symmetrical and unsymmetrical piperazinium salts can be prepared whose interfacial activity makes them suitable for use in wetting and cleaning agents and as corrosion inhibitors.

Description

R ¹ and R ² , which may be either identical or different and denote C _n H _{2n + 1} , C ₆ H ₅ , C ₆ F ₅ CH ₂ ,

R ¹ and R ² together represent CH ₂ CH ₂ -B-CH ₂ CH ₂ , wherein

BO, S, CH ₂ , NR ³ ,

RC _n H _{2n +} I, C ₆ H ₅ CH ₂ , C ₆ F ₅ CH ₂ , C _n H _{2n + 1} CO, C _n F _{2n + 1} CO, Ar _F and

η are a value from 1 to 10, as well

X is chlorine, bromine or iodine, characterized in that fluoroaromatic amines of the type

.R ¹ Ar-O-CH ₂ CH ₂ -N. ;

in which Ar means a fluoroaromatic, with alkyl halides in a molar ratio of at least 1: 1 or directly the corresponding ammonium salts are heated at a temperature of 120 to 210 ° C.

2. The method according to claim 1, characterized in that 2-pentafluorophenoxyethyl amines are used as the fluoroaromatic amines.

3. The method according to claim 1, characterized in that are used as alkyl halides aryloxy-alkyl halides.

Field of application of the invention

The invention relates to a process for the preparation of piperazinium salts. Due to their surface-active activity, the compounds prepared according to the invention are suitable for use in wetting and cleaning compositions and as corrosion inhibitors.

Characteristic of the known technical solutions

Unsymmetrical piperazinium derivatives are known and are prepared by reaction of chloroacetic acid esters with 1,4-dimethyl-piperazine (AJ Wysocki and D. Taber in: Surfactant Science Series, Vol 4: Cationic Surfactants, edited by E. Jungermann, Marcel Dekker , Inc., New York 1970, pp. 138-140). The chloroacetic acid esters are obtained by esterification of chloroacetic acid with alcohols using naphthalenesulfonic acid as a catalyst and continuous removal of water by azeotropic distillation with benzene.

A disadvantage is - apart from the complicated synthesis - and the content of carboxylic acid ester groups that are susceptible to hydrolysis. This affects the scope of the connections. Furthermore, only asymmetric piperazinium salts can be prepared by this method. A wide variation of the structure is not possible.

Object of the invention

The object of the invention is to produce piperazinium salts in a simple manner and in a generally applicable way, so that both unbalanced and symmetrical piperazinium salts become available in a wide range.

Explanation of the essence of the invention

The object of the invention is achieved by a process for the preparation of piperazinium salts of the formula

R ¹ and R ² , which may be either the same or different

and C _n H _{2n + 1} , C ₆ H ₅ , C ₆ F ₅ CH ₂ , or,. ,

R ¹ and R ² together represent CH ₂ CH ₂ -B-CH ₂ CH ₂ , wherein

BO, S, CH ₂ , NR ³ ,

R ³ C _n H _{2n +} , C ₆ H ₅ CH ₂ , C ₆ F ₅ CH ₂ , C _n H _{2n + 1} CO, C _n F _{2n + 1} CO, Ar _F and

η are a value from 1 to 10, as well

X is chlorine, bromine or iodine, according to the invention by the invention fluoroaromatic amines of the type

Ar - 0 -

in which Ar means a fluoroaromatic, with alkyl halides in a molar ratio of at least 1: 1 or directly the corresponding ammonium salts are heated at a temperature of 120 to 210 ° C.

 The occurring reaction takes place according to the following equation:

2 Ar - 0 - CH CH - N

+ 2 RX

Ar-O-CH ₀ CH,

2 X '

2X "+ 2Ar-O-R

The reaction of the fluoroaromatic amine with the alkyl halide leads to the target product via the corresponding ammonium salt. As a result, it is also possible according to the invention to obtain the piperazinium salt directly by heating such an ammonium salt at temperatures of from 120 to 21O ⁰ C.

Among the fluoroaromatic amines to be used according to the invention in which the radical Ar is a fluoroaromatic, the compounds cyclized on the N atom, such as morpholine, thiomorpholine, piperazine and piperidine, are of particular interest. Thus, in the case of piperazine by the variation of the substituent on the second N-atom, a range of new compounds can be produced. Particular interfacial activity is exhibited by piperazine-formed compounds in which R ^{3 is} a fluorinated aliphatic (C _n F _{2n + 1} CO) or fluoroaromatic (C ₆ F ₅ CH ₂ or Ar _F ) radical. Ar _F is pentafluorophenyl or compounds derived therefrom, for example CF ₃ -C ₆ F ₄ or C ₆ F ₅ -C ₆ F ₄ .

embodiments

example 1

80 g (0.28 mol) of 2-pentafluorophenoxyethyl-diethylamine are heated with 62.5 g (0.28 mol) of decyl bromide at 120 to 130 ⁰ C for 5 days. Subsequently, the precipitated salt is filtered off and washed with acetone. There are obtained 33 g (67% of theory) of a white, solid substance (melting point 270 to 275 ^° C.) whose IR and NMR spectra have the following structure:

2 Br

The water-soluble product is characterized by the reduction of the surface tension of the water in the following way: Conc. (Mol / l): 4x10 " ² 2x10" ² 1X10 " ²

σ (mN / m): 29 36 43

Example 2

80 g (0.27 mol) of N- (2-pentafluorophenoxyethylmorpholine are heated with 60 g (0.27 mol) of decyl bromide at 120 to 130 ° C. for 5 days, during which time the reaction solidifies, after extraction of the diethyl ether-soluble fraction the residue becomes acetone

washed. 46.5 g (89% d. Th.) Of the Piperaziniumsalzes obtained (melting point about 36O ⁰ C). The resulting product with the structure

2 Br

which is occupied by IR and NMR spectra, is water-soluble and reduces the surface tension of the water in the following way:

Conc. (Mol / l): 4x10 "2x10 ^{2 2} 1 x 10" ²

σ (mN / m): 28 28 33

Example 3

69.2 g (0.1 mol) of N-Pentafluorphenoxyethyl-N'-perfluorooctanoyl-piperazin be together with 18.4 g (0.1 mol) of butyl iodide for 24 hours at 120 ⁰ C heated. After extraction with ether and washing with acetone, 50.9 g (80% of theory) of a piperazinium salt of the structure remain

C ₇ F ₁₅ CO -

N - COC ₇ F ₁₅

.]

2 I

which melts at 320 ° C with decomposition and results in water has a surface tension reduction in the following manner: Conc. (mol / l): 4x10 "2x10 ^{2" 2} 1 x 10 ^"2

σ (mN / m): 20 20 25

Example 4

42.9 g (0.1 mol) of 2-octafluorodoluenoxyethyl-diphenylamine and 19.3 g (0.1 mol) of octyl bromide are heated together at 170 ° C for 4 days. After work-up as described, 22.6 g (82% of theory) of a piperazinium salt of the structure are obtained

2 Sr,

which has a melting point of 290-295 ° C and the surface tension of the water is reduced as follows: Conc. (mol / l): 4x10 ~ 2x10 ^{2 "2} 1 x 10 ^-2

σ (mN / m): 27 32 43

Example 5

38.1 g (0.1 mol) 2-Pentafluorphenoxyethyl-methyl-decylamine, and 13.5 g (0.1 mol) are heated Heptyichiorid 5 days at 150 ⁰ C. The deposited product is filtered and washed with diethyl ether and acetone. This gives 17.5 g (75% of theory) of the following piperazinium salt

2 Cl "

the aqueous solution following the reduction of the surface tension shows: Conc (mol / l). 4x10 "2x10 ² ~ ² 1 ~ ² x 10

σ (mN / m): 26 27 30

Examples

50 g (0.17 mol) of N- (2-pentafluorophenoxyethyl) piperidine and 78 g (0.27 mol) of 2-pentafluorophenoxyethyl bromide are heated at 180 ^° C. for 5 hours. The resulting crystal slurry is diluted with acetone, filtered off and washed with acetone. There are obtained 26 g (81% of theory) of white crystals (melting point above 26O ⁰ C). Based on IR and NMR spectra, the following structure was detected:

2 Br

The water-soluble product is characterized by reducing the surface tension of the water as follows: Conc (mol / l): 4 x K) - ² 2x10 ^'2 1 x 10 ~ ² only.

σ (mN / m): 29 30 35

Example 7

75 g (0.15 mol) of N- (2-Pentafluorphenoxyethyl) -N '- (heptafluortoluyl) piperazine and 108 g (0.32 mol) of 2-Pentafluorphenoxyethyliodid are heated at 130 ⁰ C for 2 days. The crystals are slurried with acetone, filtered off and washed on the filter with acetone. 166 g (60% of theory) are obtained (melting point above 260 ^° C.). On the basis of IR and NMR spectra, the following structure was proved:

CF.

2 I '

The water-soluble product is characterized by reducing the surface tension of the water in the following manner from: Conc (mol / l). 4x10- ² 2x10 ^"2 1 x 10 ^-2

σ (mN / m): 20 22 28

Example 8

72 g (0.24 mol) of N- (2-Pentafluorphenoxyethyl) morpholine and 70 g (0.24 mol) of 2-Pentafluorphenoxyethylbromid are heated at 180 ⁰ C for 6 hours. The crystal slurry is diluted with acetone, filtered off and washed with acetone. 30 g (64% of theory) of a piperazinium salt identical to those described in Example 2 are obtained.

Example 9

21 g (0.36 mol) of N, N-bis (2-pentafluorphenylethyl) piperidinium bromide are heated to 180 ⁰ C for 6 hours. The resulting crystal slurry is diluted with acetone, filtered off and washed with acetone. There are obtained 9 g (66% of theory) of a piperazinium salt (melting point above 26O ⁰ C), which has the structure of the salt of Example 6.

Example 10

42.1 g (0.1 mol) of N- (2,4-difluorophenoxy-ethyl) -N '- (pentafluorobenzyl) -piperazine are heated at 125 ° C. for 5 days with 22.1 g (0.1 mol) of decyl bromide , The precipitated salt is filtered off with suction and washed with acetone. There are 27.5 g (73.5% of theory) of the corresponding piperazinium salt of the structure

IC ₆ F ₅ - CH ₂ - N

2 Br

obtained, which melts at 290 to 295 ⁰ C. The water-soluble salt reduces the surface tension in the following manner: Conc. (Mol / l): 4χ10 ' ^{2 2} × 10 -2 ixiO ²

σ (mN / m): 21 22 26

Claims (2)

claims: ,1 ".' "1 R " R ^£ 1. A process for the preparation of piperazinium salts of the formula 2 X