SK68692A3 - Method of imines preparation - Google Patents

Abstract

Imines (azomethines, aldimines, ketimines) so-called Schiff's bases are prepared direct from aromatic nitro- or nitrosocompounds by acting of minimum one carbonyle compound, chosen from aromatic cycloalifatic or alifatic aldehydes and ketones and carbonaceous oxid at temperature 60 to 220 degrees of Celsius and pressure 0,3 to 30 MPa. Carbonylic condensation catalyzes system consisting of elementary sulfur or sulfur compound with molecular weight 34 to 98 gmol/exp -1/ (H/sub_2/S, COS, CS/sub_2/) in mass 0,1 to 10 per cent weight counted for nitrocompounds and nitrosocompounds. Next innorganic (NaOH, KOH, CH/sub_3/COONa, CH/sub_3/COOK, CH/sub_3/ONa,...) or organic aprotic nitrogeneous base (trialkylamines, pyridine, alkylpyridine) in mass 0,1 to 50 per cent weight and compound of bivalent to pentavalent vanadium in mass 0,001 to 3 per cent weight.

Description

Technical field

The invention relates to a process for the preparation of imines (azomethines, aldimines, ketimines), the so-called. Schlff bases. from nitroaromatics or from nitrosaromatics and organic carbonyl compounds, in particular aromatic and cycloaliphatic aldehydes and ketones, catalyzed by carbonylation condensation with carbon monoxide.

BACKGROUND OF THE INVENTION

Imines (azometins, aldimines, ketimines) Schiff bases.

used primarily as intermediates, have long been prepared by condensation of aldehydes as well as ketones with primary aliphatic, cycloaliphatic and aromatic amines (Deák G .: Minor Reactions in Organic Chemistry, p. 332, Alfa. Bratislava 1980. Schiff H .:

Justus Liebigs Ann. Chem. 140, 1867, p. 93. 148. 1868. p. 330, 201, 1880, p. 355. 210, 1881, p. 114. Cordes F. H. Jencks W. P .:

J. Am. Chem. Soc. 84. 1962. p. 832). Aldehydes, in particular aromatic aldehydes and primary amines, in an alkaline medium form aldlmine (Schiff's base). Step 1 of the reaction

will create addition imí n compound , from which with spontaneous elimination R rnh ₂ R OH -H ₂ O R _x \ \ / \ C - 0 --- i- C - C - N - R / / \ FROM H H N - • H H

Thus, the effect of aromatic aldehydes on aniline with water separation results in anils or so-called anilines.

Schiff bases Hj5 _C6-NH2 + 0 = CHC ₆ H _o

→ C _e H _e N = CHC _e H 5 +

H ₂ O, in particular benzylideneniline.

benzaldehyde, or benzanline. Similarly, benzophenone and aniline) c.

Benzenenonani in (Reddelien G .: Ber. 42. 4759 (1909). 43, 2476 (1910). Billman JH, Ta KM: J. Org. Chem. 23 535 (1958). Chemische Experiment, i erlLunst,. Russian translation: Eksperimenta methods in organičeskoj chimii. 470.

Izd. Chimija ". Moscow (1969). Cram, D.J., Hammond, G. S., Organic Chemistry, p. 405. Academia Prague (1969). Kováč J .. Kováč 5 .: Organic Chemistry, p. 394. Alfa. Bratislava 1977). The reaction proceeds at relatively low temperatures, but the azometins formed are still only then. when formed from an aromatic aldehyde and an aromatic primary amine of sufficient alkalinity. Schiff bases, prepared from aliphatic amines, have a C = N reactive bond and are capable of further reaction. Similarly to azometins. prepared from an aliphatic aldehyde and an aromatic amine, very easily, e.g. polymerize. to form cyclic triamines and the like.

However, despite the technical simplicity of the methods for preparing imines from primary amines and aldehydes or ketones, for some targeted imines, starting primary amines are difficult to obtain. Catalytic deoxygenation of organic compounds with carbon monoxide solves this problem. direct synthesis of Schiff bases from aromatic derivatives. aldehydes. respectively. ketones and carbon monoxide, e.g. from nitrobenzene. benzaldehyde and carbon monoxide

Catalyst + 3 CO --------------?

solvent

+ 3 ° C> 2 forms benzalinin at 170 ° C. 5 MPa under the catalytic action of noble metal compounds VIII. groups such as carbonyl rhodium and the interaction of pyridine (Igbal, A.F.M .: J. Org. Chem. 37, 1972, p. 2791). However, the disadvantage is the difficult-to-reach catalyst and the need for high purity carbon monoxide.

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The invention is a process for preparing imines. called.

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SUMMARY OF THE INVENTION

The essence of this

Scheme bases of aromatic nitro compounds and / or and / or nitroso groups by treatment with at least one organic carbonyl compound selected from aromatic cycloaliphatic and aliphatic aldehydes and ketones under carbon monoxide pressure

0.3 to 30 MPa. at 60 to 220 ° C.

optionally in the presence of an aprotic solvent, carried out so. 2. The process according to claim 1, characterized in that the carbonylation condensation is catalyzed by a catalytic consisting of elemental sulfur and / or a compound (II) of 2 molecular weight in the system, having from 0.1 to 98 gmol ^-1 in an amount of 0.1 to 10% by weight. in an amount of 0.1 up to t

e is the mass and / or inorganic and / or organic base in the pentavalent vanadium mass. and / or the compounds bivalent to an amount of 0.001 to 3% by weight.

hydroxides%

The inorganic base is selected from alkaline metals, in particular sodium hydroxide, potassium hydroxide and lithium hydroxide.

optionally their precursors, such as sodium oxide, alkali metal alkoxides, in particular potassium methoxide to pentoxide.

sodium, methoxide to pentoxide precursors, such as alkali metals together. to C <s. Then alkaline salts weak /

such as sodium acetate to sodium valerate, to potassium valerate.

potassium or aliphatic carboxylic acid alcohols.

potassium acetate as well as mixtures of C ₂ to C ₆ sodium salts of carboxylic and hydroxycarboxylic acids. (a) resulting from the manufacture of cyclohexanone; and. cyclohexanol by oxidation of cyclonexane or fatty acids by oxidation of paraffins.

The organic bases consist of organic aprotic nitrogen compounds with at least one tertiary nitrogen per molecule, in particular tri-alkylanines having 1-5 carbon atoms, then leyclohexylamine. Among the heterocyclic compounds, it is primarily pyridine. methylpyridines, dimethylpyridines, methylpyridines and the like.

The catalyst system component is either elemental sulfur and / or comonomer sulfur compounds, in particular carbonylsulfide, and hydrogen sulfide, methanethiol. dimethylsulfide, carbon disulphide. Vhpdný. is ammonium. Less suitable, but useful, is sodium hydroxide, which is also a donor of inorganic base.

Of the divalent to pentavalent vanadium compounds, the most preferred are the reaction-soluble compounds, ammonium, vanadium chloride, vanadium oxychloride such as metavanadate and the like.

An advantage of the process of this invention is the production of Schiff bases.

In the present invention, it is possible to pre-reduce the aromatic aromatic nitro compounds to primary amines, i.e. directly from the CO nitro compounds or nitroso compounds, to reduce the available, even carbon monoxide, content.

without an exhaled gas source, technically demanding preparation and refining. Even the carbonylsulfide and hydrogen sulphide contained in the carbon monoxide will at least partially substitute the need for deliberately adding sulfur or a low molecular weight sulfur compound.

as a component of the catalyst system of carbonylation condensation. Last but not least, the technical raw material and economic availability of components of the catalytic system, its high efficiency, easy regenerability and insensitivity to catalytic poisons.

The process according to the invention, in which virtually all aromatic nitro- and nitroso compounds containing at least one nitro- or nitroso compound per molecule can be used in addition to carbon monoxide as the starting compound. even more than two groups, if safety reasons so allow, in terms of polynitro explosion characteristics. respectively.

polyn itroso compounds. From aldehydes with aromatic and cycloaliphatic selectives to Schiff bases of aliphatic aldehydes.

best yields are obtained with aldehydes. Significantly lower is achieved when used

The process can be carried out continuously. semi-continuously and continuously.

Further data on the implementation of the method of production of the so-called. The Schiff bases of the invention as well as other advantages are apparent from the examples.

DETAILED DESCRIPTION OF THE INVENTION

Example 1:

In a rotating (240 ipm) stainless steel autoclave, <p ^(c m objemgiijbOO ^{and the} navážl 100 GNI nitrobenzene.: 1.00 g of benzaldehyde, 10 g of triethylamine with mixture of 12:54 wt.% Water. 0.1 g of ammonium metavanadate. Fo closing the autoclave, adds ig of hydrogen sulphide and carbon monoxide admixed with .1.4% by volume of hydrogen, 0.1% by volume of oxygen or 0.6% by volume of nitrogen, to a pressure of 12 MPa, then the contents of the autoclave are heated to 150 ° C. 0.732 moles of nitrobene reacted: 0.43 moles were identified

0.46 mol of benzaldehyde and iron (azomethine). specifically

j. the conversion of n itrobenzene is 92.8

%. benzaldehyde 48.8%; and Schift base selectivity

58.1%.

Example 2:

Do autoclave. as specified in Example 1, weigh 50 g of trobenzene with an admixture of 0.027 ° s. water. 100 g of benzene 1 de'nyd. 10 g triethylamine. 0.1 g of ammonium metavanadate, and the conclusion of the autoclaving \ ^r in 1 g of hydrogen sulfide. The initial pressure of carbon monoxide, as described in Example 1, is 13 MPa. Reaction temperature 150 ± 2 ° C and time 4 h. Then, after cooling the autoclave to temperature, it is isolated. temperature

48.6 ° C. conversion

71.3% and selectivity

74.6%.

the room reaches

Bar. The Schtff base is melted and the isolated nitrobenzene reaches the benzaldehyde range of it

Example 3:

The procedure is analogous to Example 2. only nitro-benzoates (50 g) are examined for other nitroaromatics in the same weight, 100 g of benzaldehyde, 10 g of triethylamine are used in all experiments. 0.1 g ammonium metavanadate and initial carbon monoxide pressure at

The results of the isochronous experiments (4 h), depending on the type of nitroaromatate, in particular the conversion of nitroaromatic and selectivity to the corresponding imines, are summarized in Table 1.

Tab. 1

Nitroaromate used 1 conversion n i troaromate Se1ekt i vi ta to the answer. Schi- e (¾) ff base øimín) (¾) o-nitrotoluene 97.5 87.3 • p-nitrotoluene 98.1 89.2! 4-chloro-l-nitrobenzene 79.3 73.8 4-methoxy-1-nitrobenzene 84.7 76.8

Example 4 ·

Do autoclave. as described in Example 1, weigh 50 [mu] l of nitrobenzene, 100 g of acetaldehyde. 10 g of triethylamine, 0.1 g of ammonium metavanadate. 1 g of hydrogen sulfide and carbon monoxide is passed at room temperature to a pressure of 10 MPa. The reaction temperature is 140 ± 2 ° C and the reaction time is 4 h. Nitrobenzene conversion reaches 100%. however, the selectivity to aldimine was only 49.3%. which appears to be the result of a significant course of side and subsequent reactions.

Example 5:

The procedure is analogous to Example 4, except that 3 g of elemental sulfur is weighed in place of hydrogen sulphide. Nitrobenzene conversion reached 98.5% and selectivity to Schiff base, only 56.4%.

Example 6:

The procedure is analogous to Example 2. Only 1 g of sodium ethoxide and 1 g of potassium acetate are used instead of 10 g of triethylamine as a component of the catalyst system. Nitrobenzene conversion reaches 99.4% and selectivity to benzine 1-idenanine 87.9%.

Example

The procedure is analogous to Example 2. Only 1.3 g of carbonyl sulphide is used instead of 1 g of hydrogen sulphide and 0.1 g of vanadium sulphide is used instead of ammonium metavanadate. Nitrobenzene conversion reached 99% and benzalaniline selectivity 89.8

ABOUT,

Example 8:

Do autoclave. As described in Example 1, 50 g of nitrobenzene are weighed. 100 g benzophenone, 1 g sodium methoxide, 1 g potassium hydroxide. 2 g pyridine and 0.1 g vanadium pentoxide. After the autoclave was closed, 1 g of carbonyl sulphide and 1 g of carbon disulphide were added and the carbon monoxide was passed to a pressure of 12 MPa. The reaction temperature is

165 ± 3 ° C and 4 h. The nitrobenzene conversion reaches 97.3 -o and the benzophenonean selativity is 89.6%.

Example 9:

The procedure is as in Example 2. Only the temperature of the carbonylation reaction is 90 ± 2 ° C. The conversion of nitrobenzene in 67 hours and 67.5% and 67.5% and 98.5% respectively. with selectivity to benzalaniline 92.3%.

Example 10:

The procedure is similar to Example 2. Only 0.4 g is used instead of 1 g of hydrogen sulfide. pressure drop increases from 75 min to 220 min. the nitrobenzene conversion reaching 97.5% and the selectivity to benzalaniline increasing to 84.8%.

Example 11:

Do autoclave. as described in Example 1, weigh 50 g of toluene. 25 g 2,4-dlnitrotoluene. 100 g of benzaldehyde. 6 g of three isobutyl amine, 0.01 g of vanadium hydroxide and 0.02 g of vanadium. After closing the autoclave, 1 g of hydrogen sulfide still results, mWBSSB.

For example, the autoclave content is heated to 150 ° C and maintained to within ± 2 ° C continuously while this main reaction is in progress.

i. d) a pressure of 10 MPa. at this temperature, the mixture was stirred for 5 h.

The conversion of 2,4-di-nitrotoluene is practically 100% and the selectivity to dlimin is 64.9%.

Example 12:

Do autoclave. as specified in Example 1, weighing trosobenzene. 50 σ «benzene. 100 and benzaldehyde.

₄ p. Read / read trimethylamine. 0.1 g addition van. (i.e., 3 g of sulfur dioxide and 0.3 g of hydrogen sulfide after the autoclave was closed).

ammonium

Edie

39.9% hydrogen. 4.3% vol. methane. 0.07% vol. carbonyl sulfide, vol. kysiíka. 2.43% vol.

0,27% carbon dioxide and 3,7% vol. of nitrogen at a pressure of 15 MPa. Thereafter, the contents of the autoclave are heated to 140 [deg.] C. with constant rotation and maintained at this temperature to + 2 [deg.] C. for 5 h. The conversion of nitrosobenzine is 99.4% and the selectivity to benzalaniline is 89.2%.

Industrial usability

Imines, especially aldimines. but also ketimines. They are useful as products for the production of technical auxiliaries, especially corrosion inhibitors, antioxidants, pesticides. additives to polymers, etc., and are technically easy to manufacture in the chemical industry. since the starting materials, especially nitroaromatics, are available in an even wider range than aromatic amines.

In addition, it is possible to use carbon monoxide-containing exhaust gases.

Claims (3)

Claims of aromatic nitro compounds and / or i. A process for the preparation of imines n-nitroso compounds n containing one to two and / or nitro groups per molecule. by treatment with at least one selected from n-trio of an organic carbonyl compound, aromatics. cycloaliphatic and aliphatic aldehydes and ketones at a pressure of up to 220 ° C, characterized by a catalytic oxide if appropriate. of carbon monoxide 0.3 to 30 MPa, at a temperature of 60 in the presence of an aprotic solvent, that the carbonylation condensation is catalyzed by a system consisting of the elemental sulfur (A div) of the sulfur compound d of molecular weight 34 to 98 gmol ^-1. 0.1 to 10% pot. calculated on the weight of the nitroso compound of the nitroso compound, the inorganic and / or organic base and / or the amount and / or the amount 0.1 to 50% by weight. and / or divalent to vanadium compounds in an amount of 0.001 and 6% by weight. 1, characterized by. that the inorganic base of a pentavalent The process of claim 1 is selected from alkali metals and alkali metal hydroxides. alkoxides of alkali salts of weak carboxylic acids, preferably among the alkali metal alkoxides. Method according to claim 1 and 2, characterized in that. that organic f the base comprises nitrogenous bases with tertiary nitrogen, selected among i trialkylamines having 1 to 5 alkyls and / or heterocyclic nitrogen compounds, preferably pyridine.