DE1253264B - Process for the preparation of trans-1-chlorobutene- (2) and 3-chlorobutene- (1) - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

C 07c

German class: 12 ο -19/02

1,253,264
C37767IVb / 12o December 24, 1965 November 2, 1967

Process for the preparation of trans-l-chlorobutene- (2) and 3-chlorobutene- (l)

Applicant:

Chemical works Hüls Aktiengesellschaft, Mari

Named as inventor:
Dr. Wolfgang Schäfer,
Dr. Hans Niedenbrück, Mari

Hydrogen chloride and ßutadiene (1,3) react in
As is known, the presence of catalysts is always below
simultaneous formation of the 1,4- and 1,2-addition product: trans-l-Chlorbuten- (2) (trans-crotyl chloride), bp 83-84 ⁰ C, nl ° = 1.4350.. 3-chlorobutene- (l) 5
(a-methyl-allyl chloride), bp 63 to 64 ° C, nl ° = 1.4150.
Several processes for the addition of hydrogen chloride to butadiene- (1,3) have become known. To
the method of U.S. Patent 2123 504
the HCl addition in inert diluent io
average (ζ. B. glacial acetic acid) at 25 to 40 ⁰ C in the presence
of salts of polyvalent metals within 18 to
Performed 40 hours with a maximum of 84 ° / ₀ yield.
The disadvantage of this method is, in addition to the long one
Reaction time the cumbersome processing of the 15 2nd

Glacial acetic acid - hydrogen chloride - chlorobutene - mixture.

Because of the associated corrosion problems with the addition of polymerization inhibitors, the use of special materials is necessary. substantial excess of hydrogen chloride under Even after the USA. Patent 3,055,954 is an elevated pressure at temperatures of preferably described method, the hydrochloric ao 15 carried out to 50 ⁰ C. The catalysts used are the addition of butadiene in a solvent, heavy metal salts, preferably acetic acid, which dissolve with the allyl halides. Form complex compounds in the presence of a borrowed compound. The reaction catalyst, preferably copper (I) chloride, requires times to be considerably shortened and the yields of the reaction at 20 to 100 ⁰ C a time of 5 to improved. - In this process, too, 7 hours are made. Working up is not easy by adding 3-chlorobutene- (1). The chlorobutenes favor the formation of l-chlorobutene- (2). In the case of the relaxed, dark-colored reaction of this process, an inconvenient uptake product must also be quickly distilled off, since otherwise solvent-hydrogen chloride-chlorine-mixture of butene-yields is produced through confusing secondary reactions. The risk of corrosion must occur through reduction. In a second fractional use of an autoclave with a glass insert, 30 distillation will then be countered with water washed. Crude distillate separated into its components. Man

Over 90% of theory of chlorobutene mixture will be according to the procedure of patent specification 16 744 of the Office for Invention and Patents in the Soviet occupation zone of Germany, according to which the implementation of Butadien with at least 40% iger aqueous hydrochloric acid with cooling in the temperature range from -10 to 0 ° C in the presence of catalytic Amounts of, for example, copper (I) chloride takes place.

The required HCl concentration is discontinuous, sometimes in a considerable excess Post-absorption of gaseous salts. This excess goes in the work-up

of the chlorobutene mixture is lost and must be laboriously recovered with losses.

These disadvantages can arise due to the amounts of aqueous hydrochloric acid according to the invention. This acid can be avoided in accordance with procedures. It became a keeps spent catalyst and dark colored process for the production of trans-l-chlorobutene- (2)

and 3-chlorobutene- (l) found by the addition of hydrogen chloride to butadiene- (1,3), which thereby is characterized by the fact that the addition is equimodal

the reaction mixture can also be washed free of acid and salt with plenty of water after it has been let down, dry the crude product and fractionally distill it. In all procedures that have become known, the HCl addition to butadiene (1,3) in a homogeneous or heterogeneous liquid phase, optionally under Pressure and in the presence of polymerization inhibitors made; this is chlorinated water

maintain acidity. - The disadvantages of this process are that the reaction takes Cooling must be carried out and considerable

Impurities and can therefore not be used again easily.

According to the German patent specification 1 143 195

The process described, the HCl addition of 50 larer amounts of the reactants in the gas-butadiene (1,3) from the start in allyl halides, phase at 50 to 150 ⁰ C, preferably at 80 to 120 ⁰ C, z. B. 3-chlorobutene (l), as the reaction medium under in the presence of a catalyst carried out from

709 680/438

the complex compound of the chloride of a metal, which is below the calcium in the electrochemical Voltage series stands and can occur in several valency levels with an amine hydrochloride insists on activated carbon as a carrier.

To prepare the catalysts, the metal chlorides are mixed with 1 to 3 mol of amine hydrochlorides and applies the resulting complex salts to activated carbon (for preparative details see e.g. in example 1). The weight of the applied metal chlorides should be 0.5 to 15% of the activated carbon weight be.

The chlorides of all metals are suitable as metal chlorides, those below calcium in the electrochemical Voltage series stand, can occur in several valency levels and with 1 or several moles of amine hydrochloride can form complex salts. The copper chlorides are particularly suitable.

The hydrochlorides are used here as "amine hydrochlorides" of amines, hydrazines and carboxylic acid ao amides. Ammonium chloride is suitable, the hydrochlorides of primary, secondary and tertiary aromatic or aliphatic amines as well as the Hydrochlorides of substituted hydrazines and of basic carboxamides.

The contacts used according to the invention lead to excellent sales that after hundreds of Operating hours only drop slightly. It was found that the metal chlorides themselves are already on Activated carbon as a carrier, act catalytically. Commercial activated carbon also develops a certain catalytic effect Effect; very likely because of their low heavy metal content. Activated charcoal and all However, metal chloride-activated carbon contacts not modified with amine hydrochloride have a considerable amount shorter lifespan than those complexed with amine hydrochloride on activated carbon applied metal chlorides. They are therefore used as catalysts for a technical-economic Process not useful, such as the results of comparative experiments compiled in Table 1 prove.

Tabel

Comparison of the conversions to chlorobutene mixture on different contacts (1 mol of butadiene + 1 mol of HCl per liter of contact per hour, contact temperature 100 ⁰ C)

Contact

Sales after an operating time of
6 hours i 50 hours I 300 hours

Activated carbon, ash content 1.27%

10 percent by weight CuCl on activated carbon

10 percent by weight CuCl + piperidine · HCl
Activated carbon

88%
89%

23% 38%

87%

80%

The catalysts used according to the invention not only accelerate the addition of hydrogen chloride of butadiene- (1,3), but also have an isomerizing effect on the chlorobutenes formed. As shown in Example 15, both 3-chlorobutene- (I) and l-chlorobutene (2) via a contact used according to the invention, a chlorobutene mixture in which the mentioned isomers are present in a ratio of about 2: 3. As experiments 2 to 14 (Table 2) show, the same isomer ratio is present in all chlorobutene mixtures obtained according to the invention.

The simplest mode of operation of the process according to the invention is that the hydrogen chloride-butadiene mixture passes through a heated contact tube to which a cooler and a countercurrent water scrubber are attached with separator and settling tank. This immediately gives a colorless, stable, catalyst-free and none Crude product containing by-products. It consists of 3-chlorobutene- (l) and l-chlorobutene- (2) in a weight ratio of approximately 2: 3 and contains 5 to 8 percent by weight butadiene (1,3) dissolved. A roughly the same proportion of unreacted butadiene escapes in gaseous form after washing with water and can be returned in the circuit to the contact tube. The isomeric chlorobutenes are separated by Normal pressure rectification.

In a second, preferred embodiment of the method according to the invention, one can use the make use of the isomerizing effect of the catalysts and with their help either pure Prepare 3-chlorobutene- (l) or pure l-chlorobutene- (2). To do this, the hot reaction product is used directly after leaving the contact zone passed into a distillation column. Be above the dephlegmator unreacted butadiene (1,3) and hydrogen chloride removed as a mixture and into the contact zone returned. The distillate is 3-chlorobutene- (1) and the bottom product is trans-1-chlorobutene- (2) removed. Each of the two isomers can be used together with fresh butadiene-hydrogen chloride mixture be returned to the contact furnace, where according to the isomerization equilibrium Rearrangement occurs. This mode of operation allows only one of the two chlorobutenes in one process stage continuously, without pressure, almost free of catalyst and by-products quantitative yield.

example 1

100 g (1 mol) of copper (I) chloride, 90 g (1.06 mol) of piperidine and 500 ml of methanol are mixed and hydrogen chloride gas is passed in with cooling until a clear, olive-green solution of the complex compound has formed. It is diluted with 4000 ml methanol, poured over with solution 1 kg (about 51) granular activated carbon, excess methanol in a water jet vacuum and dried 12 hours at 6O distributes ⁰ C in a vacuum drying cabinet.

^{1.21 contacts are heated to about 100 °} C. in an oil-heated contact tube (1 m length, 40 mm internal diameter) and 1.2 mol of hydrogen chloride gas and 1.2 mol of butadiene (1,3) are passed in per hour Cooler and a water washing tower with separator in one

Sedimentation tank in which traces of water are deposited as a lower layer.

Unreacted butadiene is taken off in gaseous form in a side branch after the washing tower and, after passing through a CaCl ₂ drying tube, is condensed in a cold trap and weighed to determine the conversion. The crude chlorobutene mixture is withdrawn from the sedimentation tank as an upper layer. It is a colorless, durable liquid that can be separated into its pure components by normal pressure rectification. It consists of 38.2 percent by weight of 3-chlorobutene (1), 59.1 percent by weight of l-chlorobutene (2), 2.3 percent by weight of butadiene (1.3) and 0.3 percent by weight of other compounds. - To stabilize it against the elimination of hydrogen chloride, a gentle stream of nitrogen is passed into the still during the distillation,

with which one enters 2 to 4 g of propylene oxide per kilogram of crude product.

Example 2 to 14

These examples demonstrate the effectiveness of a number of different catalysts. Otherwise, the way of working is the same as in example 1. The contacts are also produced analogously to example 1 in the in Table 2 indicated molar ratios. Instead of gaseous hydrogen chloride, it was concentrated aqueous hydrochloric acid is used in the preparation of the catalysts.

The crude products obtained on the various catalysts after 40 hours were gas chromatographed analyzed. Table 2 contains the results including sales figures:

Table 2 Chlorobutene mixtures by HCl addition onto butadiene- (1,3) over various catalysts

Catalyst composition sales
in"/. Composition of the chlorobutene mixture in weight
3-chlorine woent ¹ )
1-chlorine- Others at
game Butadiene buten- (l) butene (2) 0.4 1 mole CuCl + 1 mole piperidine · HCl 90 (1.3) 36.7 56.3 0.4 2 1 mole CuCl + 1 mole ammonium chloride 81 6.6 36.7 56.2 0.3 3 1 mole CuCl + 1 mole aniline · HCl 78 6.7 35.2 57.9 0.4 4th 1 mole CuCl + 1 mole pyridine ■ HCl 84 6.6 36.3 55.2 0.4 5 1 mole CuCl + 1 mole phenylhydrazine · HCl 63 8.1 35.6 57.5 0.4 6th 1 mole CuCl + 1 mole morpholine · HCl 66 6.6 36.8 57.2 0.3 7th 1 mole CuCl + 1 mole dimethylformamide · HCl 92 5.6 37.0 56.8 0.2 8th 1 mole CuCl ₂ + 2 moles piperidine · HCl 72 5.9 37.0 57.9 2.5 9 1 mole BiCl ₃ + 2 moles piperidine · HCl 52 4.9 35.6 55.7 0.3 10 1 mole MnCl ₂ + 1 mole piperidine · HCl 56 6.2 35.8 56.4 5.2 11 1 mole of ZnCl ₂ + 1 mole of ammonium chloride 55 7.5 33.5 54.5 0.2 12th 1 mole CeCl ₃ + 1 mole piperidine · HCl 57 6.8 35.2 59.4 4.4 13th 1 mole of CrCl ₃ + 2 moles of ammonium chloride 58 5.2 35.3 54.5 14th 5.8

*) Determined by gas chromatography from
40 hours of operation.

crude reaction product washed neutral with water; Average sample after

Example 15

It should be based on the example of a CuCl-piperidine hydrochloride-activated carbon contact it can be shown that the contacts have an isomerizing effect. An equilibrium mixture is always obtained in which 3-chlorobutene- (l) and l-chlorobutene- (2) in a ratio of about 2: 3, regardless of which of the two chlorobutenes is passed through the contacts.

Attempt a)

1.21 contacts (for production see Example 1) are heated to 100 ° C. in a contact tube and 906 g (10 mol) of pure 3-chlorobutene (l) in gaseous form passed over it within 3 hours. Man received 796 g of chlorobutene mixture [in addition to 35 g of butadiene (1,3) and 32 g of hydrogen chloride].

Experiment b)

Experiment a) was carried out with 906 g (10 mol) of 1-chlorobutene- (2) repeated. 795 g of chlorobutene mixture were obtained [in addition to 40 g of butadiene (1,3) and 37 g of hydrogen chloride].

Contains the composition of the starting and end products determined by gas chromatography Table 3.

Tabel

Isomerization of 3-Chlorbuten- (l) and trans-l-Chlorbuten- (2) to a CuCl-piperidine · HCl-activated carbon contact at 100 ⁰ C

Composition in percent by weight

Experiment a) Starting product I End product ¹ )

Experiment b)
Starting product End product ¹ )

Butadiene (1,3) ..
3-chlorobutene- (l)
l-chlorobutene- (2)
Others

0.0

99.5

0.3

0.2

1.7
40.3
57.6

0.4

0.1

0.4

99.5

0.0

2.2
38.4
59.4

0.0

¹ J raw reaction product washed neutral with water.

Example 16

This example describes how the isomerizing effect according to the invention is used The catalysts used, pure 1-chlorobutene- (2) can be obtained.

The contact is produced analogously to Example 1 from 440 g of CuCl, 360 g of dimethylformamide and 111 activated carbon granules and filled into catalyst tubes (40 mm internal diameter) heated ^{to 100 ° C.} In front of the catalyst tubes there is a gas preheater in which the butadiene-hydrogen chloride mixture is heated to about 90.degree. The gas stream leaving the catalyst tube is cooled to a temperature of about 70 ° C. via a heat exchanger and passed into the upper third of a 30-tray column. Above the dephlegmator of the warm water with 6O ⁰ C is charged, unreacted butadiene and hydrogen chloride are removed and returned via the Gasvorheizer in the contact zone. (In order to exclude the accumulation of inert gases in the circuit, a small amount of the gas mixture is continuously withdrawn in a side stream, namely 0.5 to 1%, based on the butadiene used, which had a purity of 99.4%.) The top product is 3-chlorobutene- (l) boiling at 63 to 64 ° C. is continuously removed and, after evaporation in the gas preheater, returned to the contact furnace together with fresh butadiene-hydrogen chloride mixture. The bottom product-transl Chlorbuten- (2) is obtained in about 98 ° / _o purity. It contains 3-chlorobutene- (l) and butadiene as impurities as well as traces of hydrogen chloride.

250 liters of butadiene and 250 liters of hydrogen chloride gas are passed into the contact furnace per hour. After hours corresponding to a yield of 95.5 * / ₀ of theory were 324 kg trans-l-Chlorbuten- condition (2).

Claims (2)

Patent claims: 1. A process for the preparation of trans-1-CMorbutene- (2) and 3-chlorobutene- (l) by addition of hydrogen chloride to butadiene- (1,3), characterized in that the addition of equimolar amounts of the reactants in the gas phase at 50 to 150 ⁰ C, preferably at 80 to 120 ⁰ C, carried out in the presence of a catalyst which consists of the complex compound of the chloride of a metal, which is below calcium in the electrochemical series and can occur in several valency levels, with an amine hydrochloride There is activated carbon as a carrier. 2. The method according to claim 1, characterized in that the addition is carried out in the presence of a catalyst which contains 0.1 to 15 percent by weight of metal chloride, based on the weight of activated carbon. 709 680/438 10.67 © Bundesdruckerei Berlin