DE1418912A1 - Process for the preparation of esters - Google Patents

Description

The priorities of filing in Great Britain of September 28, 1960, March 23, 1961 and August 30 gust I96I are used.

The invention relates to the production of esters

It has already been suggested. Olefins, such as ethylene »means To oxidize oxygen in the presence of catalysts «which Palladium compounds and a metal compound contain «which under the reaction conditions used in more than an oxidation stage can exist, for example a compound of copper or iron. Through such procedures Xthylene can be oxidized to acetaldehyde »while higher α-olefins are oxidized to ketones, i.e. when used a higher α-olefin than Xthylen, the Saueratoff in Oxidation product mainly to a non-terminal other

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place of a terminal carbon atom bound. Ss would be advantageous if one had products with a terminal Carbon atom could receive bound oxygen. An attempt was made «to react in the presence of Perform glacial acetic acid as a solvent »However, in no oxidation product obtained from such a procedure.

It has now been found that when implementing a three or α-01efins containing more carbon atoms with a carboxylate in the presence of, for example, palladium-II chloride and an essentially anhydrous reaction medium the product contains an expected high proportion of primary ester.

Invention is therefore a process for the production of unsaturated esters proposed, wherein an at least three carbon atoms containing a-01efin, in which the structure -CH> CHg is present, in the presence of a carboxylic acid and a ionizable carboxylate is brought into contact with a palladium salt

Palladium salts which can be used in the process according to the invention can be those of a carboxylic acid, for example palladium acetate, but an inorganic salt is preferably used. for example a halide, is used, especially if the process, as indicated below, is carried out with regeneration

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leads to. Palladium-II-chloride is particularly suitable. It is advantageous in conjunction with the palladium salt to use a halide of an alkali metal, for example sodium chloride or lithium chloride *

the

It should be noted that either the carboxylic acid or the ionizable carboxylate and, in many cases, preferably both should correspond to the ester to be produced. So when the process of making an acetate is used, must either acetic acid or an ionizable acetate is present and in general it is desirable to use both. Of the ionizable carboxylates which can be used are those Alkali carboxylates are the second most important, for example Sodium, potassium and Llthiumcarboxylate for use according to of the invention particularly suitable. The ionizable carboxylates can be formed in place, for example by using an alkali carbonate3 in conjunction with the Carboxylic acid 0

According to the invention The starting materials / materials used can be unsaturated aliphatic hydrocarbons with three to 20 or more carbon atoms, for example propylene, n-butene-1, n-hexene-1, n-ooten-1, 3,5,5-trimethylhexene-1 and cracked wax a-olefins from a C _lJf ~ cut. Other olefins that can be used are aryl-substituted aliphatic olefins,

Connections with

like styrene. It is also possible ^{to use other 7} olefinic double bonds, for example unsaturated acids

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and esters, provided that these represent the moiety contain.

When carrying out the method according to the invention the reaction taking place can be explained by describing the behavior of n-octene-1. If this is done with palladium-II-chlorld and anhydrous sodium acetate in glacial acetic acid solution « would be, a product is obtained which octenyl ester, including a considerable amount of priraea ester contains.

to the method according to the invention can cover a wide range of Carboxylic acids and ionizable carboxylates are used. For example, aliphatic "monocarboxylic acids" such as acetic acid and propionic acid and higher 3 acids, such as caproic acid, be used. Optionally, aliphatic dicarboxylic acids such as adipic acid can be used. On the other hand, it is also possible to use aromatic monocarboxylic acids, such as benzoic acid, and optionally aromatic dicarboxylic acids, such as phthalic acids. In all these cases, the corresponding ionizable carboxylates can be used, and as far as dicarboxylic acids are concerned, both neutral alkali salts and acidic salts such as potassium hydrogen phthalate are used suitable »You can also use acids and acidic salts, wel * before are partially esterified, for example Kthylhydrogenphthalat, and their ionizable salts, such as Kaliueäthylphthalat. The use of dicarboxylic acids and their derivatives

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For the formation of monoesters, diesters and / or their Mixtures. Diesters such as adipates and phthalates can be produced and such compounds are particularly useful for use as a plasticizer.

It is advantageous, the time during which the olefin with the Palladium salt is in contact »to stay on course if possible and to ensure that at all times the olefin concentration in the reaction mixture is not appreciably above that which is necessary to ensure the desired rate of reaction. A low concentration of free olefin can be ensured by making the olefin as it progresses Instead of adding all of the olefin to the reaction system at the start of the reaction, continuously or stepwise Add reaction. When using olefins with four or more carbon atoms, the initial olefin concentration should be be at most 103 »of the total volume of the reaction mixture.

When performing the above-described erfindungsgeaässen In the process, metallic palladium is precipitated as the reaction proceeds. That is obviously undesirable «there the reaction stops when virtually all of the palladium has precipitated. Ss is advantageous that according to the invention To carry out the process in the presence of a redox system » which can be easily regenerated, since such a process causes the precipitation of free palladium

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is prevented · The hedox system can be an inorganic compound, for example copper (II) chloride, the dee to extracting Sster corresponding copper (II) salt or iron (III) chloride, or an organic compound, for example p-Benzoquinone, Ourochinone, or 2-Ethylanthraquinone, or one Mixture of two or more such compounds. For example, if cupric chloride is used, this will be the case reduced in the reaction to copper -! - chloride, and it is finally necessary * to reoxidize this or add a fresh amount of copper (II) chloride. Similar is the case with Using p-benzoquinone converts this into a partially reduced product and one has to use either p-benzoquinone regenerate by oxidation or add a further amount to the reaction zone. The oxidation of, for example Copper-I-chloride or a partially reduced product of p-benzoquinone can be carried out continuously by supplying a gas containing molecular oxygen to the reaction system. This gas can oxygen itself «air, a mixture of oxygen in an inert gas, such as nitrogen, or a mixture of oxygen or air with the to be converted olefin, if the latter is gaseous.

If the reaction occurs in the presence of a redox system and a molecular oxygen-containing oasis, as described above " ben, is carried out, water is generated in the reaction zone

• .y.-lst nv ··. ■ - ■. ■. . ·. ■. ■ ...;. ■ -, ·

forms. It is also evident that there is always the danger of

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The entrainment of water results from the use of insufficiently anhydrous reactants. Ea is desired, the To keep the water content of the reaction mixture as low as possible. Otherwise, under the reaction conditions, the formed Esters are hydrolyzed to the corresponding carboxyl compounds and carboxylic acids. In addition, that sits down Olefin feed under these conditions with formation of carbony compounds such as aldehydes and ketones.

It is a further characteristic of the method according to the invention » that the esters produced, especially those derived from lower olefins * under the process conditions can react further with the formation of dlesters. Although these diesters are useful compounds, they generally are less useful than the monoesters, so it is often desirable to operate that they are not essentially Extent to be formed.

The undesirable effect of water and the above-mentioned formation of diesters can at least partially be eliminated by carrying out the reaction in such a way that water and the monoesters formed follow as soon as possible Their formation can be removed. One way of achieving the rapid removal of the water is to use a high one Gas velocity. For example, when using propylene, a propylene / oxygen quenching can quickly be caused by the Reaction sya'ceaa be directed. Instead, in the case of

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Turning a higher olefin, oxygen can be passed rapidly through a reaction system containing this. In turn If propylene is used, this can be mixed with a gas containing molecular oxygen in countercurrent to a falling film of a carboxylic acid, an ionizable carboxylate, a palladium salt and a redox system Solution to be directed. In the case of olefins with a higher boiling point, a molecular oxygen-containing gas can flow in countercurrent to a falling film of a solution such as those mentioned Contains constituents together with dissolved olefin, are passed. When the reaction is carried out in this way, Water can be easily removed from the reaction system by evaporation, incidentally also the nonoester, provided that its boiling point is sufficiently low. As a further alternative, the reaction can be carried out in two vessels, the system being produced in the first and the redox system being regenerated in the second. In this case, the first vessel ester and water removed from the second vessel; so that the contact between water, sster and olefin is up a minimum and the occurrence of undesirable Reactions is therefore reduced.

Water can also be removed from the reaction system by making sure that there is a compound which forms an azeotrope with water, for example benzene.

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Improved results are obtained if the process according to the invention is carried out in the presence of one or more of the following compounds acetamide, K-methylacetamide, N-dimethylacetamide, dimethylformamide, urea, acetonitrile »eenzonitrile, dialkylsulphoxides, in particular dimethylsulphoxide and amines, provided that these under do not react with the palladium salt under the reaction conditions. The total concentration of the compound or compounds of this group is preferably 5 to 80 percent by volume of the reaction mixture. When the reaction is carried out in this way, the disadvantageous effect of water is partially eliminated, the removal of which from the reaction mixture is less important. The presence of one or more of the specified compounds also has the effect of improving the ratio of primary ester to secondary ester in the products obtained. For example, n-octene-1 was reacted with acetic acid and lithium acetate in the presence of PalladiuBi II chloriii, Lithlumchlorid and a cupric salt, and oxygen was continuously passed through the held at 100 ⁰ C He & ktionsmischung "The ASTT various compounds represented by Type obtained ratio of primary to secondary Sster is given in the table below.

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Additional ratio of primary ester t seconds

dear ester

without 0.27: 1

Benzonitrll 0.60: 1

Dimethyl sulfoxide 1.17: 1

Urea 0.72 «1

From this table, it is apparent that each of the three additives listed "resulted in comparison old of the ratio obtained without such an additive to an improvement in the ratio of primary to secondary esters.

The tendency to side reactions, especially hydrolysis, is increasing with increasing molecular weight of the related olefin from «

The inventive method can be at room temperature or at the boiling point of the reaction mixture or at any intermediate temperature. Temperatures from 50 to 160 ° C. are particularly preferred. It It is evident that the use of elevated temperatures

educated

Ren facilitates the rapid removal of / water and / or ester if so desired. The procedure can be in one wide range of pressures can be performed. Atmospheric pressure is generally useful but facilitates this Application of lower pressures removes water

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and / or esters, if so desired «. The application of however, lower Dx * üc & en easily leads to a reduction the reaction rate. On the other hand, the use of elevated pressures can reduce the reaction rate increase, however, has the disadvantage »that it requires the removal of Water and / or ester difficult. In general, pressures are in the range of from atmospheric pressure to 10 atmospheric pressure to prefer. The actual operating pressure should be selected taking the specified factors into account. .

example 1

50 g palladium-II-chloride, 46g anhydrous sodium acetate, 52 g of n-octene-1 and 200 ecm of glacial acetic acid were mixed together and refluxed for 16 hours. The Realctions Mix was then diluted with water, with 500 ecm 25 # iger Caustic soda nocfcr / alisiert, and the precipitated palladium was centrifuged off, the supernatant liquid was extracted with ether. Do drying over magnesium sulfate the ether was distilled off and left a residue of 27.9 g of an oil. This residue was distilled, and 9 fractions including a Huckstand were obtained Each fraction was identified by infrared spectroscopy and gas chromatography analyzed. Based on this analysis,

net that 6l, 5 # of the olefin had reacted. The product contained 11.5 g of octenyl ester, corresponding to a yield

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of 38 * 7 $ * based on the amount of olefin converted. In the ester product the ratio of primary to secondary ester was like 1: 1.2.

Example 2

11 g of palladium-II chloride, 43 g of propionic acid and 11.6 g of sodium propionate were heated together with stirring until the mixture boiled under reflux. At that point were. 7 g of n-octene-1 were added and the mixture was refluxed for a further 16 hours. The product was then centrifuged and the liquid layer was distilled under a nitrogen atosphere. «The distillate was neutralized _? and excess octene was removed by further distillation. The ester product remained as a residue and was hydrogenated. In this catfish 3 * 5 g of octyl propionate were obtained with a ratio of primary to secondary product of 2: 1. The amount of recovered unchanged octene was 2.9 g, so that 3 * 4 g of ester of 4.1 g of n-octene-1 had been obtained, the octene conversion thus being 59 $ and the ester yield based on the amount of converted octene was 51 $.

Example 3

A solution of the following components was prepared s

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anhydrous lithium acetate 9 * 88 g

Ltthiurachlride 0.6 g

“Racial Kopfer-II ^ chloride 3.9 g

DimethylfoiTBaeid 155 Λ g Acetic acid * 5 ^ * 6 g Palladium II chloride 0.82 g

to 100 ⁰ C dese mixture was / in a reaction vessel r _r which was equipped with a cross stirrer with a hollow shaft, through which oxygen was passed at a rate of 20 liters per hour. 90 cm of n-octene-1 was then added and the reaction was carried out for 8 hours. At the end of this time, a further 30 ecm of n-octene-1 were produced. After a total reaction time of 24 hours "during which 25 g of octene had distilled off, the mixture was allowed to cool under a stream of oxygen". The product was deposited by pouring the solution into an equal volume of cold water, whereby an oil separated out. -This oil was removed and combined with a petroleum ether extract of the aqueous solution. After drying, this petroleum-containing material was distilled, whereby three fractions were obtained:

Petra ether 33.5 g

Octene 22.3 S

Ester (90Ji) + Oeten (10g) 21.1g

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So the total weight of octene recovered was 49 »^ g * so that the remaining weight of n-oeten-1 is 36.6g" · The yield of esters (19 * Og) based on this The amount of n-octene-1 was 34.8j *. The ratio of primary to secondary ester was 1 * 9: 1.

Example 4 A reaction mixture was prepared as follows S. Palladiura II chloride 0.302 g Ethium chloride 0.312 g

anhydrous lithium acetate 3 »301 g

anhydrous copper (II) chloride 1.302 g

Acetic acid 15 * 6 ecm Dimethylformamide 54.4 cm

This mixture was heated to 109 ° C. in a reaction vessel, which was equipped with a cross stirrer with a hollow shaft, through which oxygen at a speed of 20 liters per hour was initiated. 30 ecm n-octene-1 were then added and the reaction continued for 5½ hours. The product was then poured into water and extracted with petroleum ether. The extract was analyzed spectroscopically and the presence of 8.5 g of esters was determined. Of this, jSOjf were primary ester * The amount of unreacted n-ooten-1 was not determined, so the

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Yield of esters nut * based on the amount of Octene can be expressed. With such a calculation, the yield of esters is 26.2 #, so that the yield of primary ester is 15> 7 #.

Example 5 "

A reactant mixture was prepared as follows:

anhydrous lithium acetate 5 »306 g

Lithleichloride 0.211 g

anhydrous copper-II-chlorld 1 * 303 g

Acetamide 43 »62 g

Acetic acid 16.56 g

Palladium-II-chlorld 0.315 g

This mixture was heated to 110 ⁰ C in a Reaktiohsgefäss, which was equipped with a Kreuzrlihrer with hollow shaft, which was dupöh with 20 liters of oxygen blown per hour. 21.6 g of n-octene-1 was then added and the reaction was carried out for 5 hours. The product was poured into water and marked Γν. tvol / extracted. The extract was poured onto a scanner volume ₁ and the amount of esters was determined spectroscopically. The presence of 9 * 5 g of esters was found, which corresponded to a conversion of 30% of the total amount of octene used to esters. Of these esters produced, 83 were primary esters by weight.

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A reaction system was made as follows! Palladiura II chloride 0.302 g Lithium chloride 0.333 g

anhydrous lithium acetate 3 »299 g

Copper (II) chloride 1.301 g Essgi acid 15.6 ecm Dirnethylacetamide 44.6 ecm

The mixture was heated to 104 ° C in the presence of oxygen, and n-octene-1 was added to a total of 30ccm admitted. The reaction was carried out in a closed system, with the consumed oxygen from a Gas burette has been replaced. Some carbon dioxide formed its concentration increased. After 2 1/2 hours it began to cause the precipitation of palladium. The reaction was after 4 hours terminated, and the reaction product was poured into water and extracted with petroleum ether. It was ge * found that 8.0 g of ester had formed, of which £ 70 was primary ester. No attempt was made, the crowd of unreacted »n-octene-1 to be determined, so that the yield of esters is only based on that supplied to the reaction Amount of n-octene-1 can be printed out. The calculation shows that 24,756 of this n-octene-1 had been converted to esters, the yield of primary ester being based on the amount of n-octene-11 used was $ 1 .3.

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141891

Example 7

55 *% Palla-diuffl-II-chloride and 400 cc of acetic acid was stirred at a temperature of 110 ⁰ C for 1 hour together. Then 49.2 g of anhydrous sodium acetate was added and heating continued for an additional JO minutes. At the end of this time, 25.2 g of n-hexene-1 was added dropwise. The reaction was continued with constant stirring for 16 hours, after which the product was steam distilled. The organic distillate obtained weighed 9 "6 g" was neutralized with sodium hydroxide _} and the nontransparent layer was separated off. In this way, 7.13 g of a clear, colorless oil were obtained. As found, this contained 1.8 g primary ester, 3 g secondary ester and 0.6 g ketone.

The residue from the steam distillation was centrifuged to remove precipitated palladium, neutralized with sodium hydroxide and extracted with petroleum ether. After distilling off the fan, 10.5 g of a dark oil were obtained. This oil contained 4.1 g primary ester, 4.8 g secondary ester and 1.26 ketone. Thus, in this example, 14 g of ester were obtained, of which 5.9 g were primary esters and 8.1 g were secondary esters. The boiling point of this Esterprodukts ranged from 158 ⁰ C. In addition, 1.8 g of ketone were obtained. From these results, it was calculated that the olefin conversion was 33% and the ester yield was 85%. The weight ratio of primary to secondary ester is 1.4.

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Example 8

26.7 g Palladlum-II-chlorld, 24.6 g Matrlumacetat and 200 ecm acetic acid were heated together to a temperature of 110 ° C for 30 minutes. 16.9 g of 3.55 methylhexene-1 was added over 10 minutes, and heating was continued at the same temperature for 16 hours. The precipitated palladium was centrifuged off and the remaining liquid was neutralized and extracted with petroleum ether. The resulting solution was dried and distilled to remove the petroleum ether. In this way it contained 13 * 1 g of ester, corresponding to a yield of 53%, and 0.4 g of ketone, corresponding to a yield of 1.8%, the bulges being based on the amount of olefin used was £ 54.8, and the ester yield based on the olefin converted was 97 # · In the ester product the ratio of primary to secondary ester 2, JiSl ₉ ie 7 "0Si of the ester product were primary esters.

53 × 4 g of palladium (II) chloride, 49.2 g of sodium acetate and 400 cc of acetic acid were heated together at a temperature of 110 ° C. for 30 minutes. 53 * 2 g a-01efine by a C ^ fraction were added during 10 minutes) and heating was continued C for 16 hours at a temperature of 110 ⁰ The palladium precipitate was removed by centrifugation, and the residual liquid was neutralized with Nasriumhydroxyd and

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extracted with PetrolSther. The solution thus obtained was dried and distilled to remove the petroleum. In this way, 62.5 g of product were obtained, of which 45 percent were esters . This ester had a boiling point of 142 to 186 ° C. at 5 ma Hg pressure. Upon analysis, this ester product consisted mainly of primary unsaturated esters.

Example 10

His solution was prepared as follows:

Palladium II chloride 5.52 g

Lithium chloride 1.67 g

Lithiura acetate 5 * 03 g

Copper (II) acetate 21.6 g

Dimethylformamide 150 oca.

Acetic acid 50 ecm

Propylene was 155 minutes long by maintained at 105 to 110 ⁰ C solution umgepumpt.Das product was in gebammelt held at -40 ⁰ C cold traps. The volume of the absorbed propylene was 542 cca, corresponding to 0.02 mol. The weight of the product obtained was 1.7 g. This product was composed as follows:

Allyl acetate 55 %

Isopropenyl acetate 25 %

Acrolein 5 f,

Acetone 15 %

The weight of the ester obtained was accordingly 1.36 g, corresponding to a yield of 68 #, based on the amount of absorbed propylene. As can be seen, the ratio of primary to secondary ester was 55:25, i.e. 2.2: 1. It will assumed that acrolein and acetone and hydrolysis of the esters were formed.

Example 11

A solution of 5 »0 g lithium acetate, 21.6 g of copper II acetate ^, 50 cc acetic acid and 150 cc of dimethylformamide was heated in a reaction vessel to a temperature of 105-110 ⁰ C. The system was flushed with butene-1 and a solution of 3.5 g palladium-II chloride and 1.7 g lithium chloride in acetic acid was then added. Over the next 80 minutes, 65O com butene-1 was absorbed. The reaction product was diluted with water and then extracted with petroleum ether. After the petroleum ether had been distilled off, 2.4 g of an oil remained which contained 1.2 g of butenyl acetate. This corresponds to a yield of 3θ £ of esters. The ratio of primary to secondary esters was found to be 3.9 * 1. The main product almost certainly had the structure

Example 13

There were 4 solutions each with the following together settlement made!

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Lithium acetate 3 * 30 g Lithium chloride 0.20 g Palladium II chloride 0.30 g Acetic acid 8o ecm

n-0eten-l 10 ecm

Additional additions were made to each of the four solutions as follows given:

I. 2.4g copper (II) acetate II. 2.4 g copper (II) acetate + 9.3 g benzone nitrile III. 2.4g copper (II) acetate + 10, Ig dimethyl sulfoxide IV. 1.3 g copper (II) chloride + 6.0 g urea.

Each mixture was heated to 100 ⁰ C in a reaction vessel which was equipped with stirrer a cross hollow shaft ittt / was through which oxygen at a rate of 20 liters per hour. Routed. At the end of the reaction time the products were separated and the amounts of primary and secondary esters in the ester reaction product were determined. These results are given below.

Additive Primary Ester Secondary Ester

79 % 63 * 46 % 58 *

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without 21 * Benzonitrile 37 # Methyl sulfoxide 54 % urea 42 %

ι η ι ο »ι ζ

As can be seen, »the three are related in this example Additives all have a primary to secondary ratio

% Ester »which is considerably higher than that without additives

received.

example 13th A solution was prepared as follows: Palladium II chloride 0.8 g Lithium chloride 0.56g Copper (II) chloride 3 »95g Calcium hydrogen phthalate 6.56g Phthalic acid 30 »0 g

n-octene-1 10.8 g

This mixture was heated to a temperature of 105 ° C; and oxygen was passed through at a rate of 1 liter per hour for 6 hours. At the end of this The product was then separated to give 1.3 g of olefin and 4.1 g of ester. According to the analysis, this ester product consisted mainly of diesters. Assuming that If the product was completely diester, its yield, based on the converted n-octene-1, was approximate

Example 1"

53 * 4g palladium-II-chloride became old with stirring for 1 hour 400 ecm of acetic acid heated. 49.2 g of sodium acetate were added

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added, and the mixture was heated with stirring for an additional 30 minutes. 33.6 g of styrene were slowly added from a dropping funnel and the reaction mixture was stirred continuously at a temperature of 110 ° C. for 16 hours. The mixture was then allowed to cool and then centrifuged to remove precipitated metallic palladium. The filtrate was neutralized with a concentrated sodium hydroxide solution and extracted with petroleum ether. Fractionation of the petroleum ether solution gave a dark orange-brown UI ₄ which was dried over anhydrous magnesium sulfate, filtered and weighed. The weight of the product, consisting almost entirely of esters, was 33.3 g, corresponding to an ester yield of 70 % based on the amount of styrene used -Phenyl ethyl acetate, from which it can be concluded »that the crude ester consisted mainly of ß-phenyl vinyl acetate ·

Example 15

The results of this example were obtained using a) a 30 # volume concentration of the olefin and b) a £ 10 volume concentration of the olefin. In comparison, the results show the advantage of a low olefin concentration.

BATH

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a) 0.264g palladium-II-chloride, 0.304g Llthiumchlftrid, 3.3O7g lithium acetate * 1, jjOlg copper-II-chloride, 54.5 ecm dimethyl? formamide, 15 "6 cc acetic acid and 30 cc of n-octene-1 were heated to a Teoperatur of 110 ⁰ C, with oxygen bit was passed at a rate of 20 liters per hour," The reaction for 4 hours continued and anschllessend the product was separately · On these catfish, 9.1 g of ester were obtained. On analysis of this material it was found that 59Sf of the ester was primary and the remaining 41 £ were secondary. So the ratio of primary to secondary ester was 1.44ti. The 41 # of the secondary ester consisted of 26 % acetate-2, 10% acetate-3 and 5% acetate-4.

b) In this part of the example, the same amounts of salt were used as in a). The other components were 70 ecm dimethylformamide, 20 cc acetic acid, 10 ecm n-octene ^ 1 "The reaction was carried out as described under a)" except that the total reaction time was 6 hours. A total of 5 lg of ester was obtained, of which £ 90 were primary and £ 10 were secondary. Of these 1θ £ secondary esters, 6 were acetate-2 and 4 were acetate-}. The ratio of primary to secondary ester was 9ti. As can be seen, in this part of the example a much higher ratio of primary to secondary ester than in a) above, where a · much higher concentration of n-octene-1 was present.

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Claims (1)

- 25 patent claims. 1.) Process for the preparation of unsaturated esters, thereby characterized in that an α-olefin containing at least three carbon atoms and having the structure -CRbCIU in the presence of a carboxylic acid and an ionizable carboxylate pit is brought into contact with a palladium salt. 2.) Method according to claim 1, characterized in that the palladium salt is palladium-II-chloride, j>.) Method according to claim 1 or 2, characterized in that that the reaction is carried out in the presence of an alkali halide, preferably sodium chloride or lithium chloride 4.) The method according to any one of claims 1 to 3, characterized in that the carboxylic acid and / or the ionizable carboxy lat, preferably both, correspond to the ester to be produced 5 ·) Method according to claim 4, characterized in that the ionizable carboxylate is an alkali salt, preferably one Sodium, potassium or lithium salt. 809802/0605 ~ 26 - 6.) Process according to one of claims 1 to 5, characterized in that the carboxylic acid is an aliphatic or aromatic mono- or dicarboxylic acid and the ionizable carboxylate is an alkali salt of the same acid. 7.) Process according to one of claims 1 to 6, characterized in that the α-olefin is an allphatic hydrocarbon with 3 to 20 carbon atoms, an eryl-substituted aliphatic olefin or an unsaturated acid or an unsaturated ester 8.) Method naoh one of claims 1 to 7, characterized marked »that the olefin has 4 or» more carbon atoms contains and the initial olefin concentration is at most lOjf des total reaction volume. 9 ·) Process according to one of claims 1 to 7, characterized in that the olefin as the reaction proceeds "is added continuously or in stages 10 ·) Method according to one of claims 1 to 9, characterized in that it is in the form of a redox system durohge " leads to "which preferably one or more of the connections copper-II-chlorld, which entails the sster to be established" speaking Xupfer-II ~ eals * iron-III-chloride, Durochinon, Includes 2-ethylnthraquinone and p-benzochinone. BATH ORIGINAL - 80980 2/0 60 5 11 «) Method according to claim 10» characterized in »the · A mixture of "3 gas" containing molecular oxygen, preferably oxygen itself, flows into the reaction system Oxygen with nitrogen or a mixture of oxygen or air with the olefin to be converted »is supplied. 12 ·) Method according to one of claims 1 to 11, characterized in that the water content of the Reaktlonsmlsöhung so is kept as low as possible. 13.) The method according to claim 12, characterized in »that a high gas velocity is used to rapidly remove water from the reaction system « 14 ·) Process according to claim 12, characterized in that »the olefin is gaseous and, together with molecular oxygen, in a countercurrent to a falling film is a carbon · stture »an ionizable carboxylate, a palladium corn and a liquid containing redox breath is passed "where" through water and, if necessary, at a sufficiently low level Boiling point ester can be removed from the film continuously by evaporation. 15.) The method according to claim 12, characterized in "the" a molecular oxygen containing the in the Oegenstrom with a falling PlIm an a-01efin, a carboxylic acid "an ionizable carboxylate, a Pa ₁ I lad ium aal" and a redox "system containing liquid is brought into contact " 80S8Ü2 / 0 605 BAD 16 «) Method according to claim 12« characterized in that that the reaction is carried out in two oils, with the first Qefftss of the prayers produced and from this is regenerated and in the second the redox system and cash register * is removed from the vessel. 17 ·) Method according to claim 12 * characterized in that daaa in de "reaction system a connection" which Forms an aseotrope with water, preferably benzene * is present. 18.) Method according to one of claims 1 to 17 «characterized in that» the reaction in the presence of a οβα> ■ ore of the compounds acetamide, Ν-Methylaoetejüd, II-M-methylacetamide. Dimethylformamide, urea, AoetonitMl "ÖenxonitrH, Blalkyleulfoxyde and amines vorausgesetst," € aim this not old de under the reaction conditions * Palladtafesal "react" is durehgeftihrt "the compound or compounds vorssigsweise · prosent in an amount of 5 to 80 scrolls the entire Reaktionaaisohung are present. 19 «) Method according to one of address 1 to 18, thereby characterized in that the reaction takes place at a temperature v <m Room temperature to about the boiling point of the reaction, sugswelse «between 50 and 160 ° C, and at a« pressure of Atmospheric pressure up to 10 atmospheric pressure carried out will* BAD ÖRI <3 »NAL 80 9 802/0605