DE2365451B2 - PROCESS FOR THE PRODUCTION OF N, N-DISUBSTITUTED CARBONIC ACID AMIDES - Google Patents

Description

(D

IO

wherein R _{1 represents} a straight-chain or branched aliphatic radical with 1 to 18 carbon atoms, optionally substituted by one or more halogens or phenyl radicals, a phenyl radical, a chlorophenyl radical, a dichlorophenyl radical, a nitrophenyl radical, a dinitrophenyl radical or a trimethoxyphenyl radical or an unsaturated one containing a nitrogen atom 6-membered heterocyclic radical and R ₂ and R ₃ , which can be the same or different, represent straight-chain or branched aliphatic radicals with 1 to 4 carbon atoms or phenyl radicals optionally substituted by one or more aliphatic radicals with 1 to 4 carbon atoms or together with the The nitrogen atom to which they are bonded represent a 6-membered heterocyclic radical containing one nitrogen and one oxygen atom, characterized in that a carboxylic acid of the general formula

R ₁ -C

OH

(II)

35

wherein R ₁ is defined as above, with a caibamoyl chloride of the general formula

Cl-C-N

OR ₃

(III)

45

wherein R ₂ and R ₃ are defined as above, reacted at a temperature of 100 to 300 ° C, preferably 110 to 220 ⁰ C, with elimination of carbon dioxide and the N, N-disubstituted carboxamide obtained is isolated from the reaction mixture in a manner known per se.

55

The invention relates to a process for the production of Ν, Ν-disubstituted carboxamides : r general formula

R ₁ -CN

(D

65

orin R _{1 represents} a straight-chain or branched aliphatic radical with 1 to 18 carbon atoms, optionally substituted by one or more halogens or phenyl radicals, a phenyl radical, a chlorophenyl radical, a dichlorophenyl radical, a nitrophenyl radical, a dinitrophenyl radical or a trimethoxyphenyl radical or an unsaturated one containing a nitrogen atom 6-membered heterocyclic radical and R ₂ and R ₃ , which can be identical or different, represent straight-chain or branched aliphatic radicals with 1 to 4 carbon atoms or phenyl radicals optionally substituted by one or more aliphatic radicals with 1 to 4 carbon atoms or together with the nitrogen atom, to which they are bound represent a 6-membered heterocyclic radical containing one nitrogen and one oxygen atom.

Examples of aliphatic radicals with 1 to 18, preferably 2 to 18 carbon atoms, optionally substituted by one or more halogens or phenyl radicals, for which R _{1 can} stand, are alkyl radicals such as ethyl, propyl, butyl and pentadecyl radicals, chloroalkyl radicals such as the Monochlonnethylrest, and Phenylalkylreste such as Diphenylmethyl- and Phenyläthylreste.

Examples of unsaturated 6-membered heterocyclic radicals containing a nitrogen atom and for which R _{1 can} stand are pyridyl radicals.

Examples of aliphatic radicals with 1 to 4 carbon atoms, for which R ₂ and R _{3 can} stand or by which the phenyl radicals for which R ₂ and R _{3 can} stand, are alkyl radicals, such as methyl, ethyl, Propyl and butyl radicals, and alkoxyalkyl radicals, such as methoxymethyl, ethoxymethyl and dutoxymethyl radicals.

An example of a 6-membered heterocyclic radical which has nitrogen and an oxygen atom and which can be represented by R ₂ and R ₃ together with the nitrogen atom to which they are bonded is the morpholine radical.

The compounds of general formula I include an extremely large number of important crop protection agents and medicines. The plant protection agents of the formula I are very cheap selectively herbicidal effect. Among the substances of the general formula that can be used as medicaments 1 there are sedatives or tranquillants as well as for the treatment of arteriosclerosis suitable substances and tonics or analeptics.

The compounds of general formula 1 can be used as Ν, Ν-disubstituted carboxamides, but can also be understood as acylated amines. Accordingly, there are two main ways to produce them: (1) the acylation of secondary amines and (2) the alkylation of carboxamides.

The numerous possibilities for acylation described in the specialist literature on organic chemistry of amines are practiced in Ho-Weyl, Methods of Organic Chemistry, 8, 118 (1952), summarized. Is known z. B. acylating with Carboxylic acid anhydrides or carboxylic acid esters, whereby in addition to the acylated amine a carboxylic acid or an alcohol is formed. The disadvantage of this method is that it is generally only available for primary amines with a low number of carbon atoms can be used (A. Kaufmann: Ber., 42, 3480 [1909]; H. Honeck a: Soc. 99, 428 [1911]).

The acylation can be carried out more cheaply and with a higher yield using carboxylic acid chlorides. However, this reaction is strongly exothermic and the heat of reaction must be removed in order to control the acylation. Furthermore, the hydrochloric acid formed must be bound, since this in turn reacts with the amine serving as the starting material, which reduces the yield of the reaction. In addition, the production and purification of carboxylic acid chlorides of greater chain length is laborious (Ch. E. G as pari-Am Soc, 27,305 [1902]; W. Weaver, WM Whale _V ^: Am.Soc, 69, 1144 [1947]). ^y '

In the case of primary amines and short-chain carboxylic acids, the amines can be acylated at high levels Temperatures also with carboxylic acids, the resulting water being removed continuously, e.g. B. by distilling off in an azeotropic mixture with xylene. This procedure is only available as a laboratory procedure and only applicable to primary amines, with the additional condition that the Amines and the carboxylic acid must be insensitive to heat. Acylating primary amines with Carboxylic acids in the presence of phosphorus trichloride have been described, inter alia, by M. Grimmel in J.Am. Soc, 68, 539 (1946). In this reaction, the amine forms first with the phosphorus trichloride an intermediate phosphorus compound from which the amine acylated by the carboxylic acid arises.

Acylation with phosphorus oxychloride, phosphorus pentoxide or tetramethyl phosphite and Carboxylic acids known, in which the reaction takes place via the formation of phosphoric ester amides.

HU-PS 159 044 describes the chloroacylation of secondary amines using chlorocarboxylic acids and phosphorus trichloride.

Known, even if less important in practice, is the fact that acid amides are produced by hydrolysis can be prepared from carboxylic acid nitriles (C. E η g 1 e r: Ann., 149, 306 [1869]).

The second main group of processes for the preparation of Ν, Ν-disubstituted carboxamides is the alkylation of acid amides according to the technical literature. In this case, the carboxylic acid comes first the carboxamide produced with ammonia and this then with one of the known Alkylating agents (such as alkyl halides, dialkyl sulfates or potassium alkyl sulfates) treated (A.W. T i t h e r 1 e y: Soc, 79, 393 [1901]). In some cases the acid amide is first converted to the sodium salt with sodium amide in an inert solvent implemented and then alkylated. According to this process, a monosubstituted in the first stage Acid amide are produced; this is again converted to the sodium salt, and the latter is alkylated, whereby the Ν, Ν-disubstituted acid amide is obtained.

The specialist literature deals in great detail with the carbamoyl chlorides (substituted carbamic acid chlorides) which can be prepared from primary amines by phosgenation in the cold and which are listed as intermediate products in the preparation of isocyanates. Strangely enough, however, are the carbamoyl chlorides, which originate from secondary amines in the phosgenation, as well as the further reaction of these compounds hardly publications finHpn

According to W. Price (Soc, 125, 1J5 [1924]) the carbamoyl chlorides made with secondary amines with alcohols urethanes. It is also known that they give amine-substituted urea derivatives or carbamides (H ο u b e η — W e ν 1. 8. 118 [1952]).

Further, it is known that the mentioned carbamoyl chlorides under the conditions of Friedel-Crafts reaction to react in the common solvents at temperatures from 50 to 8O ⁰ C with aromatic compounds to form carboxamides (H ο practice-We yl, 8, 380 [ 1952]).

Furthermore, DT-PS 8 75 807 describes a process for the preparation of dialkylamides of carboxylic acids by reacting dialkylcarbamoyl chlorides with carboxylic acid alkali, alkaline earth or ammonium salts or carboxylic anhydrides described. From the implementation of the free carboxylic acids is however no speech. Rather, the teaching is even given, for example the one with a dialkylcarbamoyl chloride carboxylic anhydride to be converted acetic anhydride any traces of acetic acid present, So traces of carboxylic acid, by adding acetyl chloride, so a carboxylic acid chloride, too remove. However, the use of carboxylic acid salts as starting materials has the significant disadvantage that solid by-products, which are difficult to separate, arise, which is why the purification is inevitable. The carboxylic acids used as starting materials in DT-PS 8 75 807 must also be used Salts or carboxylic acid anhydrides are only produced from the carboxylic acids. It should also be noted that in the reaction of carboxylic acid anhydrides with dialkylcarbamoyl chlorides 1 mole of carboxylic acid anhydride (for example acetic anhydride) with 1 mole of dialkylcarbamoyl chloride (for example dimethylcarbamoyl chloride) reacts, whereby 1 mol of disubstituted carboxamide in a stoichiometric reaction (for example N, N-dimethylacetamide) and 1 mol of carboxylic acid chloride (acetyl chloride) are formed. This has the disadvantage that when using carboxylic acid anhydrides for the production the same amount of disubstituted carboxamide increases the reactor volume is required. In addition, the separation of the byproducts of the carboxylic acid chlorides, especially in the case of chlorides of carboxylic acids with a longer carbon chain and of Halocarboxylic acids, too, is not easy as they are solid.

Finally, from Journal of Organic Chemistry, Vol. 28, 1963, pp. 232 to 235, in addition to the implementation of carboxylic acid alkali salts with disubstituted carbamoyl chlorides the conversion of carboxylic acids, disubstituted carbamoyl chlorides and pyridine are known. After that, the use of pyridine as a Reaction participants absolutely necessary when using carboxylic acids as starting materials, this pyridine hydrochloride with elimination of chlorine from the disubstituted carbamoyl chloride forms, whose carbon dioxide-releasing effect is well known. Since the pyridine with that of the disubstituted Carbamoyl chloride split off chlorine has to form the pyridine salt pyridine hydrochloride a stoichiometric amount of the pyridine is required. However, this brings the significant disadvantage with it that the separation of the desired product as the solid disubstituted carboxamide from

also solid pyridine hydrochloride by-product difficult and time-consuming. So the pyridine hydrochloride must with a large amount (at least the 2 times the volume) of water can be washed out, and this wash water then becomes the pyridine base released with lye and · regenerated. This brings significant additional operations and high Effort with it, which also includes the energy requirements of the distillation. When the pyridine is out its aqueous solution would not be regenerated, ι ο this would mean a loss and an accumulation of vom Lead to harmful waste water from the point of view of environmental protection.

Incidentally, is the use of pyridine as a reactant for introducing the acyl cation (with an acylpyridine complex forms) also otherwise known in organic chemistry (for example from Dr. Fodor Gabor Szerves Kemia, Vol. II, 1960, p. 1506).

The invention is based on the object, the Ν, Ν-disubstituted carboxamides of the general Formula I much simpler than previously described, practically in one stage from only two reactants without the need for purification, such as the removal of solid by-products, would be required. This was achieved according to the invention.

The invention relates to a process for the preparation of Ν, Ν-disubstituted carboxamides the general formula

OR ₁ - C - n '

(D

35

wherein R _{1 represents} a straight-chain or branched aliphatic radical with 1 to 18 carbon atoms, optionally substituted by one or more halogens or phenyl radicals, a phenyl radical, a chlorophenyl radical, a dichlorophenyl radical, a nitrophenyl radical, a dinitrophenyl radical or a trimethoxyphenyl radical or an unsaturated one containing a nitrogen atom 6-membered heterocyclic radical, and R ₂ and R may be different from _3, which are identical o ^r, denote straight-chain or branched aliphatic radicals having 1 to 4 carbon atoms or optionally substituted by one or more aliphatic residues having 1 to 4 carbon atoms substituted phenyl or together with the nitrogen atom, to which they are bonded represent a 6-membered heterocyclic radical containing one nitrogen and one oxygen atom, which is characterized in that a carboxylic acid of the general formula

60

R ₁ -C

OH

(H)

chloride of the general formula

Cl-C-N

I! \

OR ₃

(MI)

wherein R ,. as defined above, with a carbamoylworin R ₂ and R ₃ are defined as above, is reacted at a temperature of 100 to 300 ⁰ C, preferably 110 to 220 ⁰ C, with elimination of carbon dioxide and the resulting Ν, Ν-disubstituted carboxamide in an is isolated from the reaction mixture in a known manner.

The inventive method is compared to those of the prior art including those of the DT-PS 8 75 807 and from Journal of Organic Chemistry, Vol. 28, 1963, pp. 232 to 235, very surprising. It is known from organic chemistry that the carboxylic acids, their salts and the carboxylic anhydrides are not analogs, but behave differently, for example towards alcohols, alkyl halides, carbic acid chlorides and ammonia and amines, respectively. In addition, the DT-PS 8 75 807 taught teaching that the carboxylic acid is to be removed as troublesome, was found to be imperative for the person skilled in the art, that carboxylic acids with disubstituted Carbamoylchloiiden certainly not to the desired products Ν, Ν-disubstituted carboxamides are able to react, because otherwise, according to the DT-PS 8 75 807 the carboxylic acid does not have to be removed. In contrast, the finding according to the invention is that just the carboxylic acids labeled as disturbing with the disubstituted carbamoyl chlorides react in very good yield to obtain pure products, very surprising.

The surprising character of the invention compared to the prior art is illustrated by the teaching of Journal of Organic Chemistry, Vol. 28, 1963, pp. 232 to 235 that in the case of using carboxylic acids as starting materials for the implementation in addition to the disubstituted carbamoyl chlorides as further Reactant pyridine is imperative, while in the case of the use of carboxylic acids Salts the reaction with the disubstituted carbamoyl chlorides alone is still to be carried out clarified more. In the person skilled in the art, this has reinforced the conviction that distracts from the invention, that the reaction of carboxylic acids with disubstituted carbamoyl chlorides does not work per se, but detours are necessary for this, namely either the carboxylic acids have to be replaced by other reactants or additionally Respondents are to be used. In contrast, the contrary statement according to the invention, namely that the carboxylic acids themselves with the disubstituted carbamoyl chlorides without further Reactants, such as pyridine, smoothly to the desired Ν, Ν-disubstituted carboxamides react in good yield, extremely surprising.

When the carboxylic acid of the general formula II is reacted with the carbamoyl chloride of the general formula As already mentioned, formula III is formed as a by-product, carbon dioxide, and the end of the reaction is indicated by the cessation of gas evolution. The further work-up of the reaction mixture can be done as described above.

A significant advantage of the method according to the invention is that with it from easily accessible and easy-to-handle starting materials in one stage in good yield of pure N, N-disubstituted Carboxamides can be produced. It can be described as extraordinarily favorable that through the inventive method produced a wide range of Ν, Ν-disubstituted carboxamides can be. So the carboxylic acid from which they are derived can be straight-chain or branched Alkyl carboxylic acid with? up to 19 carbon atoms, but amides of halocarboxylic acids, Arylcarboxylic acids or arylcarboxylic acids substituted in the aryl radical, and also heterocyclic acids Carboxylic acids are produced. The group of secondary materials that can be used as starting materials Amine is equally extensive.

In particular, compared to the use of carboxylic acid salts as starting materials, the inventive Process the considerable technical progress with it that no solid by-products develop. This is also many times over against the use of carboxylic acid anhydrides, in particular those with a longer carbon chain and halocarboxylic acid anhydrides as starting materials are the case. The carboxylic acids used as starting materials according to the invention are also simpler than those according to the State of the art as starting materials used carboxylic acid salts and carboxylic acid anhydrides obtain. Furthermore, the process according to the invention has advantages over the use of carboxylic acid anhydrides as starting materials the considerable technical progress with it, according to the invention for Production of the same amount of disubstituted carboxamide almost 50% less Reaction device volume is required than when using carboxylic anhydrides according to the State of the art by having the molecular weight of the carboxylic acid anhydrides almost 2 times that of corresponding carboxylic acids. It also means a significant simplification that according to the invention no pyridine is used, which overcomes the disadvantages described above.

If the reaction is carried out in the absence of solvents, then there is a special one Advantage of the implementation is that the gaseous by-products from the Ν, Ν-disubstituted acid amide, which is a solid substance, escape and therefore their removal does not require any special measures requires.

The process according to the invention can be carried out batchwise, but it is special Advantage that it is also continuous in the systems commonly used in the chemical industry can be carried out. The continuous implementation only requires a packed column, a film evaporator, a precipitator and a centrifuge.

The invention is explained in more detail with reference to the following examples.

example 1

25.6 g of palmitic acid and 19.1 g of N ₁ N - (di - η - butyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The reaction mixture was ^{heated uniformly to 130 °} C. over the course of about 30 minutes, with evolution of gas beginning. The mixture was kept at 130 to 160 ^° C. for 1 hour. After this time the evolution of gas ceased. The melt was ^{poured into 100 cm 3 of} cold water and ^{extracted with 100 cm 3 of} benzene. The benzene layer was dried over sodium sulfate and then the benzene was distilled off under vacuum. The yellowish oil remaining as residue solidified to white crystals on cooling. In this way, 27.2 g (74.8% of theory) of N, N- (di-n-butyl) palmitic acid amide with a melting point of 37 ° C. were obtained.

Analysis: . N 3.83%; Calculated .. .. N 3.77%. found ...

Example 2

There were placed in a provided with a gas outlet tube 250-cm ³ flask 3.5 g of benzoic acid and 5 g of N- (isopropyl) -N- (phenyl) carbamoyl chloride was charged and heated within half an hour at 140 ⁰ C, whereby gas evolution began. The reaction mixture was held for about 1 hour at 140 to 17O ⁰ C. After this time, the evolution of gas ceased. The melt was poured ^{into 150 cm 3 of water with stirring.} The deposited crystals were filtered using a glass frit, ^{washed twice with 20 cm 3 of} water each time and then dried. 5.7 g (78% of theory) of N- (isopropyl) -N- (phenyl) -benzoic acid amide with a melting point of 55 to 56 ^° C. were thus obtained.

Analysis: . N 5.86 Calculated .. . N 5.98 found ...

Example 3

9.88 g of N- (isopropyl) -N- (phenyl) carbamoyl chloride and 5.02 g of monochloroacetic acid were placed in a 250 cm ^{3 flask provided with a gas discharge tube.} The reaction mixture was heated to 120 ° C. and kept at this temperature for 1 hour with stirring until the evolution of gas had ceased. The melt was then ^{poured into 100 cm 3 of} water. The deposited crystals were filtered off, ^{washed twice with 20 cm 3 of} water each time and then dried. 9.6 g (90.7% of theory) of N- (isopropyl) -N- (phenyl) chloroacetamide with a melting point of 76.5 ° C. were thus obtained.

Analysis:

Calculated ...
found ....

Cl 16.74, N 6.61%;
Cl 16.97, N 6.87%.

Example 4

^{Into a 250 cm 3} flask provided with a gas discharge tube, 9.58 g of N, N- (di-n-butyl) carbamoyl chloride and 10.6 g of 3,5-dinitrobenzoic acid were weighed, and then the mixture was adjusted to 140 ° C heated to 16O ⁰ C, whereby gas evolution started the reaction mixture was until completion dei gas evolution, ie for about 90 minutes, maintained at the above temperature and poured dei ³ water after Abkühler with stirring in 100 cm. Then the mixture was ^{extracted with 100 cm 3 of} benzene and the organic rails separated from the aqueous layer were dried over sodium sulfate. After the benzene had been distilled off, a residue, the nacl

609 508/47

2

short standing froze, received. 12 g (74% of theory) of N, N- (di-n-butyl) -3,5-dinitrobenzoic acid amide were thus obtained obtained with a melting point of 61 to 62 ° C.

nyl) -palmilinsüurcamid with a melting point of

Analysis:

Calculated
found .

N 13.0%;
N 12.71%.

Example 5

16.0 g of morpholine carbamoyl chloride and 22.5 g of 3,4,5-trimethoxybenzoic acid were weighed into a 500 cm ^{3 flask provided with a gas discharge tube.} The mixture was heated to 120-140 ° C. and held at that temperature for 90 minutes. After the evolution of gas had ceased, 100 cm ^{3 of} water were added and the mixture was heated to boiling under reflux conditions for 10 to 15 minutes. The reaction mixture was then filtered through a folded filter and the filtrate was cooled to 5 ° C. The precipitated crystals were filtered off using a glass frit and dried. Thus 23.0 g (82% of theory) of N- (3,4,5-trimethoxybenzoyl) -morpholine or N- (3,4,5-trimethoxybenzoyl) -tetrahydro-1,4-oxazine with a melting point of 116 ° C obtained.

Analysis:

Calculated
found .

N 4.98%;
N 4.94%.

Example 6

Analysis: . Cl 14.42, N 5.71%; Calculated .. . Cl 14.63, N 5.68%. found ...

Example 7

19.8 g of N- (isopropyl) -N- (phenyl) -carbamoyl chloride and 25.6 g of palmitic acid were placed in a 500 cm ^{3 flask provided with a gas discharge tube.} The mixture was ^{heated to 140 °} C. and then kept at a temperature of 140 to 180 ^° C. for 90 minutes. After the evolution of gas had ended, the mixture was cooled to 20 ° C., ^{treated with 20 cm 3 of} ether and the precipitated crystalline amine salt was removed by filtration. The ethereal solution was evaporated in vacuo and the residue was ^{poured into 50 cm 3 of} ice water. The product was filtered off and dried. So 31 g (84% of theory) N- (isopropyl) -N- {phe-

Analysis: Calculated ... N 3.75%;
found .... N 3.68%.

Example 8

19.1 g of N, N- (di-n-butyl) carbamoyl chloride and 12.2 g of benzoic acid were introduced into a 350 cm ^{3 flask provided with a gas discharge tube.} The reaction mixture was heated to 110 ° C., during which the evolution of gas, which lasted for about 90 minutes at a temperature of 110 to 130 ° C., began. Thereafter, the reaction mixture in 100cm ³ of water was poured and with 100 cm ^{3 of} benzene extracted. The benzene layer was separated from the aqueous layer and dried over sodium sulfate. The solvent was distilled off and the product obtained was purified by fractional vacuum distillation. 18.0 g (77.5% of theory) of N, N - (di - η - butyl) - benzoic acid amide were thus obtained. The product was a colorless oil with a boiling point of 144 ° C./14 torr.

Analysis:

Calculated
found .

N 6.0%;
N 5.95%.

Example 9

4.62 g of N, N- (diphenyl) carbamoyl chloride and 2.3 g of monochloroacetic acid were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The mixture was heated to 120 to 13O ⁰ C until the evolution of gas maintained at this temperature, which took about 1 hour to complete. The melt was then ^{poured into 50 cm 3 of} water. The precipitated crystalline substance was filtered off, ^{washed twice with 10 cm 3 of} water each time and then dried. 4.65 g (94.7% of theory) of N, N- (diphenyl) chloroacetamide with a melting point of 115 to 118 ° C. were thus obtained.

50

55 15 g of morpholine carbamoyl chloride and 12.5 g of benzoic acid were introduced into a 350 cm ^{3 flask fitted with a gas discharge tube.} The reaction mixture was heated to 150 to 160 ° C. The evolution of gas ceased after half an hour. The melt was ^{poured into 50 cm 3 of} water and then ^{extracted with 50 cm 3 of} benzene. The layers were separated and the organic layer was dried over sodium sulfate. Fractional vacuum distillation gave 17 g (89% of theory) of N- (benzoyl) morpholine or N- (benzoyl) tetrahydro-1,4-oxazine. The product was a colorless oil having a boiling point from 178 to 182 ⁰ C / 13 Torr.

Analysis:

Calculated
found .

N 8.5%;
N 8.5%.

Example 10

There were placed in a provided with a Gasableitungsrohi 500-cm ³ flask unc 24.6 g of nicotinic acid 28.5 g N, N- (diethyl) carbamoyl chloride is introduced The reaction mixture was heated to 190 to 22O ⁰ C, it hitzt and about 20 to 30 Minutes to the end of de: gas evolution held at this temperature. The brown melt was separated by vacuum distillation. The fraction at 155 to 160 ° C / 10 torr transitions was collected. In this way, 31.0 g (87.5% of theory) of N, N- (diethyl) nicotinic acid amide or nicotinic acid diethyl amide were obtained.

Analysis:

Calculated ... N 15.7%;
found N 15.3%.

2

Example 11

1.25 g of diphenylacetic acid and 1.0 g of NN-f-dimethylJ-carbamoyl chloride were introduced into a 100 cm ^{3 flask provided with a gas discharge tube.} The reaction mixture was heated to 120 to 14O ⁰ C 'long held 2 hours / at this temperature. Thereafter, the cooled to 8O ⁰ C melt was poured into 20 cm ³ of water. The precipitated crystals were filtered off, washed with a little water and then dried. Thus 1.4 g (100% of theory) (N, N-dimethyl) - [l, l- (diphenyl) - acetamide] or 1,1 - (diphenyl) - N ₁ N - (dimethyl) acetamide were with obtained a melting point of 128 to 129 ° C.

Analysis:

Calculated
found .

N 5.85%;
N 5.96%.

Example 12

N 6.65, Cl 16.8%;
N 6.41, Cl 16.21%.

Example 13

There were placed in a provided with a gas outlet tube 250-cm ³ flask 31,3g 4-Chlorbenzocsäure and 27.1 g N, N- (diethyl) carbamoyl chloride introduced, and the mixture was in the oil bath for 30 minutes at 140 to 160 ⁰ C heated. After cooling, the reaction mixture was ^{poured into about 200 cm 3 of} water and then ^{extracted with 100 cm 3 of} petroleum ether. The petroleum ether was distilled off from the organic layer under vacuum. 32 g (76.5% of theory) of N, N- (diethyl) -4-chlorobenzoic acid amide or 4-chlorobenzoic acid diethylate were obtained in the form of a yellow oil.

Analysis:

Calculated ...
found ....

N 6.65, Cl 16.8%;
N 6.35, Cl 16.6%.

14th

example

19.1 g of 3,4-dichlorobenzoic acid and 13.5 g of N, N- (diethyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The mixture was heated on the oil bath at 14Ö to 16O ⁰ C and 30 minutes held at this temperature. After cooling, the reaction mixture was ^{poured into 100 cm 3 of} water and then ^{extracted with 50 cm 3 of} petroleum ether. The organic layer was dried and the solvent was removed. In this way, 22 g (89.5% of theory) of N, N- (diethyl) -3,4-dichlorobenzoic acid amide or 3,4-dichlorobenzoic acid diethylamide were obtained in the form of an orange-colored oil.

, Analysis:

Calculated ..
found

31.3 g of 2-chlorobenzoic acid and 27.1 g of N, N- (diethyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The reaction mixture was heated to 130-140 ° C. and held at this temperature for 45 minutes. The cooled mixture was ^{poured into 200 cm 3 of} water and then ^{extracted with 100 cm 3 of} benzene. The benzene layer was dried over sodium sulfate and then the benzene was removed by distillation in vacuo. 38 g (90.5% of theory) of N, N- (diethyl) -2-chlorobenzoic acid amide or 2-chlorobenzoic acid diethylamide were obtained in the form of a yellowish-brown oil.

Analysis:

Calculated ..
found

N 5.70, Cl 28.8%;
N 5.41, Cl 28.4%.

Example 15

19.1 g of 3,4-dichlorobenzoic acid and 19.1 g of N, N- (diisobutyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The mixture was heated to 140 ° C and 30 minutes held at 160 to 18O ⁰ C. After cooling, the melt was ^{poured into 100 cm 3 of} water. The deposited crystals were filtered off using a glass frit, ^{washed twice with 20 cm 3 of} water each time and then dried. The crude product was recrystallized from petroleum ether. 25 g (83.5% of theory) of N, N- (diisobutyl) -3,4-dichlorobenzoic acid amide or 3,4-dichlorobenzoic acid diisobutylamide with a melting point of 74 to 76 ° C. were obtained.

Analysis:

Calculated ..
found

N 4.68, Cl 23.6%;
N 4.78, Cl 24.07%.

Example 16

15.5 g of 2-chlorobenzoic acid and 19.1 g of N, N- (diisobutyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The mixture was melted and held at 140 to 160 ^° C. for 30 minutes. After cooling, the reaction mixture was ^{poured into 100 cm 3 of} water and then ^{extracted with 50 cm 3 of} petroleum ether. The organic layer was dried and the solvent was distilled off under vacuum. Thus, 22.5 g (85.5% of theory) of N, N - (diisobutyl) - 2 - chlorobenzoic acid amide or

- 2-chlorobenzoic acid diisobutylamide in the form of a dark red Obtain oil.

Analysis:

Calculated
found .

N 5.30, Cl 13.35%;
N 5.41, Cl 12.94%.

Example 17

19.1 g of 3,4-dichlorobenzoic acid and 19.1 g of N, N- (disec.butyl) carbamoyl chloride were introduced into a 250 cm ^{3 flask provided with a gas discharge tube.} The mixture was ^{heated to 120 °} C. and kept at a temperature of 120 to 130 ^° C. for 30 minutes. After the evolution of gas had ceased, the reaction mixture was ^{poured into about 100 cm 3 of} water, the N, N- (disec.butyi) -3,4-dichlorobenzoic acid amide or 3,4-dichlorobenzoic acid disec-butylamide separating out in solid form . The product was filtered using a glass frit, washed 2mai with 20 cm ³ of water and then dried To 24 g (80% of theory) of product were obtained with a melting point of 176 to 18O ⁰ C.

^J analysis:

Calculated ... N4.68, Cl23.6%;
found .... N 4.45, Cl 24.07%.

Example 18

There were placed in a provided with a gas outlet tube 250-cm ³ flask 25.6 g of N - [(2-Mcthyl-6 - ethyl) - phenyl] - N - (ethoxymethyl) - carbamoyl chloride and 10 g of monochloroacetic acid introduced to 120 ⁰ C and held at 120 to 140 ° C for 30 minutes. After the evolution of gas had ceased, the reaction mixture was ^{poured into 50 cm 3 of} water and extracted with 50 cm ^{3 of} benzene. The benzene layer was separated and evaporated. Thus 22 g (82% of theory) N - [(2-methyl-6-ethyl) -phenyl] -N- (ethoxymethyl) -chloroacetamide were obtained in the form of a dark yellow oil.

Analysis: . N 5.2, Cl 13.3%; Calculated .. . N 5.03, Cl 12.97%. found ...

Example 19

There were placed in a provided with a gas outlet tube 250-cm ³ flask, 29.8 g of N - [(2,6-diethyl) -phenyl] - (N-buloxymethyl) carbamoyl chloride and 10 g Monochloressigsäurc introduced, heated to 120 ⁰ C. and held at 120 to 140 ° C for 30 to 40 minutes. The reaction mixture was worked up in the manner described in Example 18. Thus, 25 g (80.5%, of theory) [N- (2,6-diethyl) phenyl] -N- (butoxymethyl) chloracelamide were in the form of a? Obtain dark brown oil.

Analysis:

Calculated
found .

N 4.51, Cl 11.4%;
N 4.39, Cl 10.9%.

Claims (1)

Claim: Process for the preparation of N, N-disubstituted carboxamides of the general formula Il, R ₁ -CN R,