WO1983004020A1

WO1983004020A1 - Method for the preparation of amino-cetonitriles

Info

Publication number: WO1983004020A1
Application number: PCT/EP1983/000118
Authority: WO
Inventors: Georg L. Busch; Hans-Peter Meier
Original assignee: Cemona Ag
Priority date: 1982-05-18
Filing date: 1983-05-06
Publication date: 1983-11-24
Also published as: IT1163385B; CH646140A5; IT8321155A0; ES8505513A1; EP0109406A1; IT8321155A1; ES522516A0

Abstract

The compounds having the formula (I), wherein R is: -H, -CH2?CN, -CH2?CH2? -N(CH2?CN)2?, -CH2?CH2?-N(CH2?CN)-CH2?CH2?-N(CH2?CN)2? or -CH2?CH2?-NH-CH2?CH2?-NH-N(CH2?CN)2? are prepared by reacting ammonia ethylenediamine or diethylenetriamine with the formaldehyde and the cyanhydric acid. The process is characterized in that, as catalyst, aminoacetic acid is used which is also used for the preparation of acetonitrile of formula I. Aminoacetic acid has the formula (II), wherein R' is: -H, -CH2?COOH, -CH2?CH2?N(CH2?COOH)2?, -CH2?CH2?-N(CH2?COOH)-CH2?CH2?-N(CH2?COOH)2? or -CH2?CH2?-NH-CH2?CH2?-N(CH2?COOH)2?.

Description

- -

Process for the preparation of aminoacetonitriles

The invention relates to a process for the preparation of aminoacetonitriles, in particular nitrilotriacetonitrile (NTAN), iminodiacetonitrile (IDAN), ethylenediamine-tetraacetonitrile (EDTN), diethylenetriamine-pentaacetonitrile (DTPAN) and diethylenetriamine-tetraacetonitrile of the general formula (I)

R-N (CH CN) I,

where R -H, CH ₂ CN, -CH CH -N (CH_CN)

-CH ₂ CH ₂ -N (CH ₂ CN) -CH ₂ CH ₂ - (CH ₂ C) ₂ or -CH ₂ CH ₂ -NH-CH ₂ CH ₂ - (CH ₂ CN)

means the intermediates for the preparation of the complexing agents nitrilotriacetic acid (NTA), iminodiacetic acid (IDA), ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA) and diethylenetriamine tetraacetic acid. - i. -

These complexing agents are conquering ever more fields of application in the most varied fields of technology, for example also in the detergent industry, where they suppress the cheap but wastewater-polluting phosphates.

Prerequisites for such applications are a cheap price and an environmentally friendly method of manufacture, in particular which does not pollute wastewater or is only slightly polluting.

The production of these complexing agents by reacting ammonia, ethylenediamine or diethylenetriamine with monochloroacetic acid, for example according to DE-PS 718 981 (1942), has long since become uneconomical. The cyanomethylation of ammonia, ethylenediamine or diethylenetriamine with formaldehyde and hydrocyanic acid in an acidic medium is more advantageous, for example according to DE-AS 1 112 081 (1961) and GB-PS 1 342 ^* 045 (1973). This process leads to pure end products, since the poorly soluble acetonitriles (NTAN, IDAN, EDTN, DTPAN) can be isolated in good yields as intermediates.

The reaction of ammonia or amine with formaldehyde and hydrogen cyanide to the desired acetonitriles of the general formula I is only possible in the presence of a strongly acidic catalyst. As such, sulfuric acid is usually used: DE-PS 1 177 646. About 3 mol% of sulfuric acid are required. In this way, acetonitriles of the general formula I are obtained in high yields of over 90% of theory. However, this procedure shows considerable

O PI Side effects of sulfuric acid have disadvantages. In the presence of this acid, not only is the formation of the aminoacetonitrile catalyzed, under its condensing and oxidizing action, complex, strongly colored condensation and addition products are formed from hydrocyanic acid and also from formaldehyde. This gives rise to dark to black mother liquors which can neither be reused nor get into the waste water since they contain non-degradable poisons. They have to be neutralized with burnt lime, evaporated and burned in special plants. As a result, the economics of the production process for the aminoacetonitriles are significantly reduced.

After it has been shown that replacement of sulfuric acid by weaker organic acids such as acetic acid and formic acid reduces the yield considerably, to half to two thirds, it was proposed that strong organic acids of pKa <_3, such as maleic acid, oxalic acid, phthalic acid, be used as the catalyst To use malonic acid etc.: JP-OS 51-108 018 (1976) (Chemical Abstracts 8__ 120808s). The use of such acids actually leads to less strongly colored mother liquors. However, these strong organic acids contaminate the product, which in particular when the mother liquors are reused leads to considerable levels of foreign substances which cannot be accepted and / or after them Load the sewage systems accordingly. In addition, they can lead to malfunctions in the production process due to precipitation.

OMPI

^■ It has been found that the purity and waste water problems are eliminated if the aminoacetic acid that is desired as the final end product is used as the catalyst. Surprisingly, these acids, in similar molar concentrations {- * 3 mol%), were just as effective as sulfuric acid, but did not cause discoloration of the product and mother liquors. On the contrary, they bind traces of heavy metals due to their metal-complexing action which could otherwise cause staining.

After concentrating and supplementing the lost amounts of aminoacetic acid, the mother liquors from Hessen often use themselves repeatedly. Due to their low solubility in water, these are acidic. Catalysts hardly interfere with the wastewater and in the product, since this is saponified in the same compound anyway in the next reaction step «,

Accordingly, for example, nitrilotriacetonitrile is obtained in the highest yields by reacting ammonia with formaldehyde and hydrocyanic acid in the presence of nitrilotriacetic acid as a catalyst. The nitriloacetonitrile obtained contains slightly more than half of those used. Nitrilotriacetic acid. The rest is in the mother liquor. After evaporation and replacement of the nitrilotriacetic acid (NTA) separated off with the nitriloacetonitrile by fresh NTA, this is used again as a catalyst in the subsequent batch, etc. The reuse can be repeated at least 4 to 5 times. - -

In exactly the same way, ethylenediaminetetraacetonitrile (EDTN) is obtained in yields of 95 to 98% of theory if ethylenediamine, formaldehyde and hydrocyanic acid are reacted in the presence of about 3 mol% of ethylenediaminetetraacetic acid (EDTA). Here too, the mother liquor can be reused after evaporating and supplementing the EDTA separated with the EDTN. The reuse can be repeated a few times.

The process for the preparation of aminoacetonitriles of the general formula (I) by reacting ammonia, ethylenediamine or diethylenetriamine with formaldehyde and hydrocyanic acid is accordingly characterized in that the catalyst comprises the aminoacetic acid of the formula I belonging to the acetonitrile of the formula I to be prepared (II)

R'-N (CH COOH) ₂ II,

wherein R ^' -H, -CH ₂ COOH, -CH ₂ CH ₂ "N (CH ₂ COOH) ₂ ,

-CH CH.-N (CH ₂ COOH) -CH CH - (CH COOH) or -CH ₂ CH ₂ - H-CH ₂ CH ₂ -N (CH ₂ COOH)

means used.

Accordingly, nitrilotriacetic acid (NTA) is used as a catalyst for the production of nitrilotriacetonitrile (NTAN), ethylene diamine tetraacetic acid (EDTA) is used for the production of ethylenediaminetetraacetonitrile (EDTA), and for the production of diethylenetriaminepentaacetonitrile (DTPAN) is used as a catalyst diethylenetriaminepentaacetic acid. (DTPA) used.

example 1

Nitrilotriacetonitrile

Ammonia is ^"converted by reaction with formalin in hexamethylene lentetramin.

1 mol of hexamethylenetetramine is stirred with about 14 mol of hydrocyanic acid and 8 mol of formalin. Now add 12 g of nitrilotriacetic acid (NTA) as a catalyst and allow the mixture to react completely.

The product is filtered off and dried. It contains 510 g nitrilotriacetonitrile ^"(NTAN), which are 95% of theory, and 8 g of nitrilotriacetic acid (NTA). The Mut¬ terlauge is evaporated, the evaporation residue with 8 g of fresh NTA added and used in subsequent approach with equal success as a catalyst .

Example 2

Ethylenediaminetetraacetonitrile

60.1 g of ethylenediamine (1 mol) are added dropwise with stirring at 0 to 10 ° C. with 193 g of 35% formaldehyde solution (2.25 mol), 1,4,6,9-tetraaza- tricyclo [4,4,1,1 4'9] dodecane. Now be 124 g of hydrocyanic acid (4.5 mol) are passed into the reaction mixture at 0 to 20 ° Celsius. 8.8 g of ethylenediaminetetraacetic acid (EDTA) (30 mmol) are then added. The catalyst quickly dissolves in the reaction medium. Within about 30 minutes, a further 193 g of 35% aqueous formaldehyde solution (2.25 mol) are allowed to pour in. With a strongly exothermic reaction, ethylenediaminetetraacetonitrile forms. The product is filtered off and dried. It consists of 210 g of ethylenediaminetetraacetonitrile (that is 97% of theory) and 7.2 g of ethylenediaminetetraacetic acid.

The mother liquor is evaporated. The residue contains 1.6 g of ethylenediaminetetraacetic acid. In the next same batch, it is fresher after being mixed with 7.2 g

Ethylene diamine tetraacetic acid was used again as a catalyst.

This gives 213 g of product which contains 207.4 g of ethylenediaminetetraacetonitrile (this is 95.9% of theory) and 5.6 g of ethylenediaminetetraacetic acid.

The mother liquor is evaporated, 5.6 g of fresh ethylenediaminetetraacetic acid are added, and the approach is used again as a catalyst, etc.

Table s. Page g.

OMPI, lPO table

Production of EDTN by reaction with EDÄ with CH_0 + HCN in the presence of EDTA and reuse of the mother liquor

Batch or yield of EDTA in the product EDTA in the use EDTN in% of the mother liquor in%

% of the theoretical rate of use

1. 97 82 18

1. Again. 95.9 63 37

2. Again. ■ 98.1 47 53

3. Again. 95.5 28 72

4. Again.

Example 3

Diethylenetriaminepentaacetonitrile

1 mol of diethylene triamine is mixed with 6 mol of formalin and hydrocyanic acid. The reaction is started by adding 12.6 g of diethylenetriaminepentaacetic acid ITPA (32 mmol). A product is obtained which contains 286.5 g of diethylenetriamine-pentaacetonitrile (this is 96% of theory) and 8.3 g of DTPA.

After evaporation and the addition of 8.3 g of DTPA, the mother liquor can be used with practically the same success as a catalyst for the subsequent same batch.

Ol PI t / λ Example 4

In a manner similar to that described in Example 1, iminodiacetonitrile which contains small amounts of EDA is obtained by reacting ammonia with a little formalin and hydrocyanic acid in the presence of iminodiacetic acid (IDA). After evaporation and replacement of lost EDA, the mother liquor can be used as a catalyst in the subsequent batch.

Example 5

In a similar manner to that described in Example 3, the reaction of 1 mol of diethylenetrimain with 4 mol of formalin and 4 mol of hydrocyanic acid in the presence of about 10 g of diethylenetriamine tetraacetic acid gives the diethylenetriamine tetraacetonitrile in good yield, which contains traces of diethylenetriamine tetraacetic acid.

The mother liquor can be used repeatedly after evaporation and addition of the lost diethylenetriamine tetraacetic acid.

O PI

Claims

fPatent claim

1. Process for the preparation of aminoacetonitriles of the general formula (I)

RN (CH ₂ CN) ₂ I,

wherein R is -H, -CH CN, -CH CH -N (CH CN),

-CH CH -N (CH CN) -CH CH -N (CH ₂ CN) ₂ or -CH ₂ CH ₂ -NH-CH ₂ CH ₂ -N (CH ₂ C)

means, by reacting ammonia, ethylenediamine or diethylenetriamine with formaldehyde and hydrocyanic acid, characterized in that the aminoacetic acid of the formula (II) belonging to the acetonitrile of the formula I to be prepared is used as the catalyst

OMPI Λ _% T / VIFO - -

R '-N (CH ₂ COOH) ₂ . II,

wherein R \ -H, -CH COOH, -CH CH N (CH COOH).,

-CH ₂ CH ₂ -N (CH ₂ C00H) -CH ₂ CH ₂ -N (CH ₂ C00H) ₂ or -CH ₂ CH ₂ -NH-CH ₂ CH ₂ -N (CH ₂ COOH) ₂

means used.

2. Process for the preparation of nitrilotriacetonitrile (NTAN), ethylenediaminetetraacetonitrile (EDTN) and diethylenediaminepentaacetonitrile (DTPAN) according to patent claim 1, characterized in that the catalyst used is in each case the aminoacetic acid associated with the acetonitrile, that is to say nitrilotriacetic acid (NTA) tetraacetic acid (NTA), ethyl _. (EDTA) or diethylenetriaminepentaacetic acid (DTPA) used.

3. Process for the preparation of NTAN, according to claim 2, characterized in that the catalyst used is NTA.

4. Process for the production of EDTN, according to patent claim 2, characterized in that EDTA is used as the catalyst.

5. Process for the preparation of DTPAN, according to patent claim 2, characterized in that DTPA is used as the catalyst.