DE1161878B - Process for the production of O-vinyl compounds - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Class: C 07 c

German class: 12 ο -19/03

Number: 1161 878

File number: F 36624 IV b / 12 ο

Filing date: April 21, 1962

Opened on: January 30, 1964

It is known that compounds such as alcohols, phenols or carboxylic acids, which are a reactive Containing hydrogen atom bonded to oxygen, reacts with acetylene to form the corresponding Implement vinyl compounds. In this way, vinyl ethers or vinyl esters are obtained. The reaction can be carried out in the gas phase or in the liquid phase without pressure or under pressure. In all cases the presence of a catalyst is required. In the vinylation of alcohols, alkaline ones have been found Agents such as sodium hydroxide, proven; Carboxylic acids can be especially in the presence vinylate catalytic amounts of the corresponding zinc or cadmium salts. In some cases you can zinc and cadmium compounds as well as caustic alkalis are used.

Temperatures between 120 and 220 ° C. are required for these reactions. Lower boiling compounds can therefore only be vinylated under pressure in the liquid phase.

A disadvantage of this vinylation process is the insufficient activity of the used Catalysts off. Response times of 48 hours and more are often required. Through this unwanted side reactions are often promoted, or the resulting sensitive vinyl compounds are polymerized in spite of added inhibitors.

There has now been a process for the preparation of O-vinyl compounds from hydroxyl-containing compounds organic compounds and acetylene at elevated temperatures and pressures in Found presence of alkali, zinc or cadmium compounds, which is characterized in that the reaction in the presence of 0.005 to 0.5%> based on the weight of the vinylated Starting compounds, small amounts of a finely divided noble metal of Group VIII. The noble metals often cause a considerable increase in the reaction rate working in the absence of precious metals under otherwise identical conditions. So you can By adding finely divided precious metals, the vinylation time can be reduced considerably. Another The advantage of the presence of precious metals is that some compounds, for example phenols substituted by terpene residues, which so far only vinylated in the presence of caustic alkalis could be vinylated according to the invention with the help of zinc compounds, which is why is desirable because a vinylation with zinc or cadmium compounds in general Process for the preparation of O-vinyl compounds

Applicant:

Farbwerke Hoechst Aktiengesellschaft

formerly Master Lucius & Brüning, Frankfurt / M.

Named as inventor:

Dr. Günther Jacobsen,

Dr. Heinz Späthe, Frankfurt / M.-Höchst

runs under gentler conditions than with caustic alkalis.

Compounds containing hydroxyl groups which are suitable for the reaction according to the invention The following processes may be mentioned: Carboxylic acids, especially aliphatic carboxylic acids with 4 to 10 carbon atoms, for example valeric acid, caproic acid and 2-ethylhexanoic acid, also aromatic carboxylic acids such as benzoic acid, but also derivatives of benzoic acid, in which nuclear Hydrogen atoms through lower alkyl groups, chlorine atoms, nitro groups and other substituents, which are inert to the reaction conditions are substituted; Phenols, for example 2,4,6-trichlorophenol, but also phenols that are substituted by one or more terpene residues, for example the reaction product of 1 mole of phenol and 3 moles of camphene; Alcohols, for example Ethyl alcohol.

The noble metals of Group VIII of the Periodic Table are suitable as noble metal catalysts, among them especially palladium. Instead of the metals, you can also use compounds of these metals use, provided they can be reduced under the reaction conditions and in the course of the reaction pass into the free metals. In this case, palladium chloride is used in particular.

309 807/436

at
game To be vinyled
link Solution
middle catalyst Pd-containing
additive Tempe
rature 160 Reaction
Time total
the
pressure
waste Vinyl-
link Boil
Point Distillation
Residue Yield to
Vinyl-
link
in % ⁰ C 160 hours at ° C / Torr the theory Ί
Ib j 20Og 2,4,6-tri-
chlorophenol - 10 g zinc acetate 10 g Pd carbon 180 y 180 6th
25th 43
44 185g vinyl-2,4,6-tri-
chlorophenyl
190 g of ether > 110/10 ■ 31
28 82
84 ² Ί 500 g of product
1 mole phenol
and 3 moles 1000 g xylene 25 g zinc acetate 2 g of Pd carbon 180 j 180 4th 11 524 g vinyl
link - - 99 2b j Camphene - ί 180 9 0.8 - - ■ - ■ - 3.1
3b I 200 g Valerian
acid - 4 g zinc oxide 1 g of Pd carbon 150 19th 44
33 140 g Valerian
114 g acid vinyl
ester \ 88/100 42
41 56
45 4a 1
4b J 200 g 2-ethyl
hexanoic acid - 4 g zinc oxide 1 g of Pd carbon 30th 48
31 183 g 2-ethyl
143 g hexanoic acid
vinyl ester . 65/15 40
69 78
61 5a \
5b j 143 g of benzoic acid 300 g of toluene 3 g cadmium
oxide 1 g PdCl ₂ 4 ₂ { 92
22nd 101 g benzoic acid
31 g vinyl ester } 81/10 j 64
116 58
18th Ov Ov
he ρ 150 g of benzoic acid 300 g of toluene 3 g zinc oxide 7.5 g Pd carbon
(5%) 18th 54
5 91 g benzoic acid
vinyl ester
9g 1 81/10 77
144 50
5 7a j
7b ■ 500 g of benzoic acid 1000 g of toluene 10 g zinc oxide 10 g Pd carbon 18th 50
20th 393 g
Benzoic acid
254 g of ^vin y ^lester 1 81/10 < 242
291 65
46 8a ¹
8b 200 g of ethyl alcohol - 4 g of potassium
hydroxide 1 g of Pd carbon 28 42
9 117 p
^B vinyl ethyl
_{25 g of} ether 1 36/760 < 24
23 37
23

If the free metals are used from the outset, these are expediently placed on suitable carriers on. All known types of activated charcoal such as Α charcoal, sugar charcoal, bone charcoal can be used as carrier material and charcoal can be used. Also suitable - especially when mixed with activated carbon - also pumice powder, silica gel, bleaching earth (e.g. kieselguhr), various types of clay and the like porous material, aluminum oxide, rutile or zirconium oxide, which are added in variable amounts can. The noble metals are expediently in amounts between 0.005 to 0.5% and are advantageous between 0.01 and 0.1 percent by weight, based on the starting compound to be vinylated, is used.

In addition to the noble metals, alkali compounds are used as catalysts in a known manner, for example caustic soda or caustic alkali, or zinc or cadmium compounds, e.g. B. zinc oxide, Cadmium Oxide or Zinc Acetate. Mixtures of these metal compounds can also be used.

The mixed catalyst consisting of these metal compounds and the noble metal can after completion The reaction can be separated from the reaction mixture by filtration and reused.

The reaction temperatures are expediently in the range between 100 and 220 ° C., advantageously between 120 and 200 ° C.

One works in general at pressures between 1 and 50 atmospheres, advantageously between 10 and 20 atmospheres.

In many cases, the use of an inert solvent, for example toluene or xylene, advantageous. In general, however, one works without a solvent.

The vinylations are either discontinuous in a pressure vessel or continuously Carried out with the help of a flow tube.

An advantageous embodiment of the process is as follows: The compound to be vinylated is filled into a pressure vessel together with the catalyst and optionally the solvent. Then the air is displaced from the reaction vessel by repeatedly injecting nitrogen and releasing the pressure. Eventually a print of set for example 5 to 15 atmospheres nitrogen, the mixture with shaking or stirring on the Brought reaction temperature and injected pure acetylene up to the pressure at which the reaction should be carried out, for example 15 to 30 atmospheres. Acetylene is now through the Reaction consumed continuously. The pressure that drops as a result is replaced by fresh pressure Acetylene brought back to the reaction pressure initially set. This is repeated so many times until the sum of the pressure drops corresponds to the acetylene consumption calculated for the conversion. After cooling, the reaction mixture is worked up by filtration and distillation.

In some cases, especially in the vinylation of carboxylic acids, the desired ones also occur Vinyl compounds as byproducts of ethylidene compounds, which result from that the starting product is added to the vinyl compound already formed in a molar ratio of 1: 1. Are such compounds are formed, then they are in the still bottoms, which also Vinyl polymers, in some cases can also contain unchanged starting material.

The O-vinyl compounds produced according to the invention are valuable intermediate products and can be polymerized and co-polymerized.

Examples

The examples are summarized in the following table. Each example consists of two Parallel approaches a and b. These are carried out under the same conditions with the only difference that the a-approach also contains palladium. By comparing the results of the respective Parallel approaches a and b can be the beneficial effect of palladium in terms of reaction time and Recognize the yield of vinyl compound.

In the table there is only one information about the corresponding approaches a and b made if they are identical. The vinyl compound yield is a percentage of theory indicated and based on the weight of the starting compound to be vinylated.

A total pressure of 20 at is always used; the partial pressure of nitrogen is 5 at (measured at 20 ° C).

When working under the conditions described, the conditions for handling are important to prevent accidents to take applicable safety measures with acetylene under increased pressure.

Claims (2)

Patent claims: 1. Process for the preparation of O-vinyl compounds from organic compounds containing hydroxyl groups and acetylene at elevated levels Temperatures and elevated pressures in the presence of alkali, zinc or cadmium compounds, marked by the fact that the reaction is carried out in the presence of 0.005 up to 0.5%, based on the weight of the starting compound to be vinylated, of a finely divided one Noble metal of group VIII or one reducible to the noble metal under the reaction conditions Compound of a noble metal of Group VIII. 2. The method according to claim 1, characterized in that the noble metal or noble metal compound Palladium or palladium chloride is used. 309 807/436 1.64 © Bundesdruckerei Berlin