DE1051269B - Process for the preparation of 1,1,3-tri- (2-halo-alkoxy) -alkanes - Google Patents

Description

GERMAN

The inventive method for the preparation of l, l, 3-tri- (2-halo-alkoxy) -alkan the general formula

K ₃ K ₁

Method of manufacture
of 1,1,3-tri- (2-haloalkoxy) alkanes

Marg I. R ₁ / -CH-CH O —C— C-X Ri I. H I. I. I. X —C —C - 0 - C- R «\ H ■ ι I. R ₈ Ra R ₅ R ₃ I. O Q ( : —Χ

HR ₂

in which X stands for halogen, R ₁ , R ₂ and R ₃ for hydrogen or a low molecular weight alkyl group, R ₄ for hydrogen or an alkyl group and R ₅ and R ₈ for hydrogen, chlorine, bromine or a low molecular weight alkyl group ao is characterized that at least 3 moles of a 1,2-alkylene halohydrin of the formula

R ₁ R ₃
X — C — C — OH

R ₈ H

in which X, R ₁ , R ₂ and R _{3 have} the above meaning, with 1 mol of an α, α S-unsaturated aldehyde of the formula

R ₄ -C = CH-CHO

R ₈

in which R ₄ , R ₅ and R _{e have} the above meaning, is reacted at temperatures from 0 to 170 ^° C. in the presence of an acidic catalyst and, if appropriate, an inert solvent.

In the reaction according to the specification, in addition to the l, l, 3-tri- (2-haloalkoxy) alkanes obtained as the main product of the above formula as a by-product are the alkoxylated aldehydes of the general formula

R ₁ R ₃ R ₄

I I I

X-C-C-O-C-CH-CHO

Applicant:

Union Carbide Corporation,
New York, NY (V. St. A.)

Representative:

Dr. W. Schalk and Dipl.-Ing. P. Wirth, patent attorneys, Frankfurt / M., Große Eschenheimer Str. 39

Claimed priority:
V. St. v. America March 11, 1953

Howard Russell Guest, Charleston,

and Harry Adams Stansbury Jr.,

South Charleston, W.Va. (V. St. A.),

have been named as inventors

R ₂ H

R ₅

in which X, R ₁ to R _{8 have} the above meaning.

The compounds prepared according to the invention are valuable intermediates for the preparation of others Products. They are good solvents for various lubricating oils and greases, such as those made by metals must be removed after painting or paving with other metals. They can also be used as crosslinking agents used in the manufacture of certain synthetic rubbers of the polysulphide type (thiocol) will.

Ethylene chlorohydrin (2-chloroethanol) and propylene chlorohydrin (l-chloropropanol-2) are necessary for the procedure particularly useful and give compounds which are particularly useful as crosslinking agents for the preparation certain types of synthetic rubber are suitable. Other useful halohydrins are ethylene bromohydrin, 1 - bromopropanol - 2, 1 - chlorobutanol - 2, 2-chloropropanol-1 and 2-chloroisobutanol-1.

Although acrol is preferred as the α, / ί-unsaturated aliphatic aldehyde for the present process
Crotonaldehyde and 2-methylacrolein are used

but other aldehydes, such as 2-chloroacrolein, can also 2-bromoacrolein, 2-ethyl-3-propylacrolein, 2-ethylacrolein, 2-chlorocrotonaldehyde, 2-bromocrotonaldehyde and 2-ethylcrotonaldehyde, find application.

Preferably, the process is carried out such that the unsaturated aldehyde is gradually added in small amounts to the dry or anhydrous alkylene halohydrin which contains a small amount of an acidic reaction catalyst. The process works best when an excess of halohydrin is used. The reaction temperature required to achieve the highest yields depends on the reaction components used. Thus, ethylene chlorohydrin reacts with acrolein slightly at 40 ^c C, but lower temperatures may as 1O ⁰ C are used, while for the fast reaction with 2-ethyl-3-propylacrolein a temperature above 5O ⁰ C and a longer reaction time are required. At temperatures above about 17O ⁰ C the efficiency of the reaction by formation of byproducts is greatly reduced, ao After completion of the reaction, the catalyst by addition of a dry alkaline compound such as sodium acetate, is neutralized and the reaction mixture was then fractionated under reduced pressure to obtain the desired compounds distilled.

Very useful catalysts are e.g. B. hydrochloric acid, sulfuric acid, phosphoric acid, hydrobromic acid and the stronger organic acids such as toluenesulfonic acids, halogenated acetic acids, and oxalic acid. Formic acid and acetic acid are also effective. It can also be those often contained in the chloroalkanols Traces of hydrochloric acid are sufficient to start the reaction without a catalyst having to be added directly got to.

The reaction can be carried out in the presence of an inert solvent for the reactants, such as carbon tetrachloride, Benzene, toluene, dibutyl ether, hexane and the like, although excellent yields of the desired products can be obtained in the absence of inert solvents. After the reaction interrupted by neutralization and destruction of the acidic catalyst by means of sodium acetate or the like has been, the water formed in the acetal formation can be removed in the subsequent distillation of the reaction mixture in the first run. In the examples part of the water is distilled off as a heterogeneous, azeotropic mixture with unchanged aldehyde, while the rest of the water is distilled over as a homogeneous, azeotropic mixture with the excess of ethylene halohydrin will.

The water formed during the reaction can be removed according to its formation by a Mixture of the aldehyde, ethylene halohydrin, hydrogen halide catalyst and an inert solvent, like benzene, refluxed at atmospheric pressure, the condensate is in a The sheath is allowed to separate, the water layer is removed and the benzene layer is refluxed into the Column is returned until no more water is separated in the separator. The. mixture is then blunted to destroy the catalyst with sodium acetate and then to recover the desired products fractionally distilled. According to another embodiment, a mixture of the Aldehyde, ethylene halohydrin, sulfuric acid catalyst and anhydrous sodium sulfate with stirring heated for several hours. The water then forms hydrous sodium sulfate, which is separated off by filtration will. The filtrate is then neutralized to destroy the acidic catalyst and then fractionally distilled.

It is known that ct, /? - unsaturated aldehydes let react with alcohols to alkoxy-substituted aldehydes or 1,1,3-trialkoxyalkanes, but it was it is not to be expected that this reaction will also proceed in good yield with 1,2-alkylene halohydrins would. It was to be feared that, on the one hand, the halogen atom in the halohydrin was caused by the formation of the acetal resulting water would be saponified or that epoxidation of these halohydrins would occur.

The invention is illustrated by the following examples:

example 1

In a mixture of 1610 g (20 mol) of anhydrous ethylene chlorohydrin and 15 cc 37 ⁰ Z ₀ IGCR hydrochloric acid were stirred at 40 to 47 ° C over 35 minutes 236 g (4 moles) of 95 ^ο / ^ β5 acrolein dropwise. After a further hour, ^{17 g of anhydrous sodium acetate were added at 40 °} C. to remove the catalyst and the mixture was fractionally distilled under vacuum. After removal of the unaltered raw materials and the water ° / ₀ yield 3-tri- (2-chloroethoxy) propane was dissolved in 66 l, l, having the following characteristics:

Weight percent
IHI

Cl

Boiling point at

5 mm Hg

⁰ C

Specific blowing
20/20 ⁰ C

Found ..
Theoretically

38.8
38.6

6.5
6.1

36.1
38.1

155

1,250

1.4714

Further, in 26 ° / ₀ yield 3- (2-chloroethoxy) propionaldehyde was obtained with the following characteristics:

Equivalence

weight as

Aldehvd

Weight percent
CIH

Boiling point at

J.0 mm Hg

⁰ C

specific weight
20/20 ⁰ C

Found ..
Theoretically

145
136.5

44.3
44.0

6.8
6.6

81

1.153

1.4444

Example 2 (4 mol) anhydrous crotonaldehyde within 30 mi

registered grooves. The mixture was whole

Stirred in a mixture of 1890 g (20 mol) of anhydrous for 8V2 hours at 60 to 65 ° C and then for 32 hours Propylene chlorohydrm and 22.6 g (0.62 mol) dry at 25 ° C. Then they were used for elimination Hydrogen chloride was stirred at 54 ° C, 280 g 70 of the hydrogen chloride catalyst 54 g (0.66 mol) of water

free sodium acetate added; the mixture thus obtained was fractionated under reduced pressure distilled, l, l, 3-tri- (2-chloroisopropoxy) butane with obtained the following properties:

Weight percent

I H I

Cl

Boiling point at
2 mm Hg

⁰ C

specific weight
20/20 ° C

Found ..
Theoretically

49.3
46.5

7.5
7.5

28.9
31.7

138

1.131

1.4650

In addition, 3- (2-chloroisopropoxy) butyraldehyde was obtained with the following properties:

Weight percent
IH

Cl

Boiling point at
3 mm Hg

⁰ C

specific weight
20/20 ⁰ C

"30 °

Found ..
Theoretically

53.6
50.1

7.8
7.9

21.2
21.6

65

1.061

1.4719

The yield of 3- (2-chloroisopropoxy) butyraldehyde was 12% and the yield of 1,3-tri (2-chloroisopropoxy) butane 14% based on crotonaldehyde. The efficiency of the reaction with respect to these two products, based on the converted crotonaldehyde, was 49%.

Example 3

In a mixture of 7 g of concentrated sulfuric acid (0.143 equivalents) and 1228 g of ethylene chlorohydrin (9.6 mol) were added with stirring at 25 to 4O ⁰ C over 5 minutes 174 g (1.92 mol) of 2-chloroacrolein. After löstündigcm standing at 25 ⁰ C and 5 hours, heating to 60 ⁰ C, the catalyst was made ineffective anhydrous sodium acetate by addition of 15 g (0.18 mol). The mixture was then fractionally distilled under reduced pressure in a packed still. There were 224 g of 2-Chlorl, l, 3-tri- (2-chloroethoxy) propane as a colorless liquid mm at a pressure of 5 Hg boiling at 162 to 170 ⁰ C. The connection had the following properties:

specific weight

20/20 ⁰ C

Molecular refraction

Found ..
Theoretically

45.8
45.2

1.321

1.4864

68.3
68.2

In addition, 81 g of 3- (2-chloroethoxy) -2-chloropropionaldehyde were obtained in the form of a colorless liquid which boiled at 81 to 83 ° C. under a pressure of 3 mm Hg column and had a specific gravity of 1.345 at 20/20 ° C , a refractive index "if = 1.4874 and a molecular refraction at 20 ⁰ C of 36.5 (theoretical 36.7) had.

The yield of 3- (2-chloroethoxy) -2-chloropropionaldehyde was 25% and the yield of 2-chloro, 1,3-tri- (2-chloroethoxy) propane 37%, each based on 2-chloroacrolein. The efficiency of the reaction with respect to these two products, based on the 2-chloroacrolein reacted, was 85%.

Example 4

In 1610 g of freshly distilled ethylene chlorohydrin of 98.5% purity, which contained 0.015 percent by weight of hydrogen chloride (20 mol) and was kept at 40 ° C., 231 g (4 mol) of 97% acrolein were added dropwise with stirring over a period of 30 minutes. It was. Stirring was continued for 6V for ₂ hours at 40 to 43 ° C and then for 7V for ₂ hours at 62 ° C. At this point the analysis indicated that the solution contained 0.040% hydrogen chloride and 0.96% acrolein. 1.7 g (0.021 mol) of anhydrous sodium acetate were then added to the reaction mixture and this was fractionally distilled under reduced pressure, l, l, 3-tri- (2-chloroethoxy) propane (56% yield) and 3- (2- Chloroethoxy) propion

aldehyde (27% yield) obtained with a 90% efficiency of the reaction based on the acrolein became.

Claims (2)

Patent claims: 1. A process for the preparation of 1,1,3-tri- (2-halo-alkoxy) -alkanes, characterized in that at least 3 moles of a 1,2-alkylene halohydrin are mixed with 1 mole of a.jS-unsaturated aliphatic aldehydes at temperatures from 0 to 170 ⁰ C in the presence of an acidic catalyst and optionally an inert solvent. 2. The method according to claim 1, characterized in that the unsaturated aldehyde is gradually added to the reaction mixture in small amounts will. Considered publications: French Patent Nos. 853 607, 698 832; U.S. Patent No. 1,902,070; German Patent No. 706,935; Gnamm: solvents and plasticizers (1950), Pp. 45, 59, 83, 87, 89, 98/99, 174, 184, 205, 233, 248 to 251, 383/384; Marchionna: Butalostic Polymers, 1946; Industrial Engineering Chemistry, 43, pp. 625-629 (1951). © 80 »767/510 2. 59