DE870698C - Process for the production of hydroquinones - Google Patents

Description

Process for the preparation of hydroquinones It has been found that by the action of iron or cobalt carbonyl and water or organic, Compounds containing hydroxyl groups on acetylenic hydrocarbons or their Substitution products in the presence of basic substances hydroquinone or his Can produce substitution products.

There are organic compounds containing hydroxyl groups especially alcohols and phenols. The acetylenic hydrocarbons can be on a or be substituted on both sides. You can z. B. of the following compounds go out: methyl, dimethyl, hexyl, vinyl, isopropenyl, phenyl or diphenylacetylene, Diacetylene, also alkynols, such as propargyl alcohol, butyne-3-o1-2, butyne-2-diol-i, q, hexyne-3-diol-2, 5, and functional derivatives of alkynols, e.g. B. ethers, furthermore nitrogen- or sulfur-containing compounds, e.g. B. i-Dimeth5-1-aminopropin-2, i-Diethylaminopropin-2, 2-Dimethylaminobutin-3, 2-n-Butylaminobutin-3, i, 4.-Tetramethyldiaminobutin-2, r, 4-Tetraethyldiaminobutin-2, 2 - Cyclohexylaminobutin-3, 2 - Dicyclohexylaminobutin-3, 2-phenylaminobutyne-3 or butyne-3-thiol-2.

Instead of iron or cobalt carbonyl, carbon dioxide can also be used in the presence of iron or cobalt compounds that are subject to the reaction conditions -to lead the carbonyls. Organic bases are particularly suitable as basic substances, such as mono-, di- or triethanolamine, morpholine, salts of dimethylaminoacetic acid, unsaturated bases, such as those produced by the reaction of tertiary amines or their salts with compounds of the acetylene series or their hydrogenation products.

The reaction is carried out continuously or batchwise, advantageously at a slightly elevated temperature, e.g. B. 4o to 1ao °. Increased pressure is only in use of gaseous acetylenic hydrocarbons or derivatives are required. It is however, it is advisable to also use liquid starting materials under a slight excess pressure inert gas, e.g. B. nitrogen, to process the ingress of air that the implementation disrupts, prevent. The reaction can also be carried out in the presence of catalysts like Raneynickel.

Under the influence of the basic substances, carbonyl is formed from the metal Metal carbonyl hydrogen as an intermediate. One can use the hydrogen compound also produce before the implementation and instead of the carbonyl on the starting materials let absorb; in this case a basic compound is also used not necessarily required.

The parts given in the following examples are parts by weight.

Example i A mixture of 19.6 parts of iron pentacarbonyl, 80 parts of water and 2o parts of monoethanolamine is in a shaking autoclave at 6o to 75 ° below a pressure of ig to 22 atm with a mixture of 2 parts by volume of acetylene and i Part by volume nitrogen treated. The consumed acetylene is made by repressing supplemented by fresh acetylene. The reaction has ended after about 24 hours.

The product is made by distillation under reduced pressure of low Freed amounts of unchanged iron pentacarbonyl.- The liquid residue is to Removal of precipitated iron carbonate, iron hydroxide and complex iron carbonyl compounds filtered, then acidified with dilute sulfuric acid and extracted with ether. After distilling off the ether from the extract, 4 parts of hydroquinone are obtained Melting point 16g °, obtained pure by recrystallization from toluene or acetone will. Based on the iron pentacarbonyl used, the yield is 18.2% Theory.

The acidic solution treated with ether becomes after neutralization with barium hydroxide, the monoethanolamine was recovered by distillation.

Example 2 20 parts of iron pentacarbonyl, 16 parts of methylacetylene, 8o Parts of water and 2o parts of monoethanolamine are in an autoclave under one pressure shaken from 5 atm nitrogen at 8o to go ° for 12 hours.

The product becomes unchanged after 3.5 parts have been distilled off Methylacetylene was taken up in methanol and the precipitated by filtration Ferrocarbonate freed. The filtrate is acidified to Congo with 50% sulfuric acid Reaction acidified, diluted with water and distilled. After removing the methanol An aqueous and an oily layer are formed. The aqueous, acidic layer becomes extracted with ether, the extract dried and freed from ether by distillation.

A yellow crystalline mass is obtained, which after washing with Melting chloroform and recrystallizing from water at 2o8 °, in ether, acetone and methanol is easily soluble in ligroin and cyclohexane, on the other hand, and the Shows constitution of 2,5-dimethylhydroquinone. The yield is 6 parts.

Example 3 2o parts of iron pentacarbonyl, 16 parts of dimethylacetylene, 80 parts of water and 20 parts of monoethanolamine are placed in a stainless steel pressure vessel Shaken under a nitrogen pressure of 18 at for 12 hours at 'Zoo to 100 °.

The product becomes unchanged after 2.5 parts have been distilled off Dimethylacetylene was taken up in methanol and the precipitated by filtration Ferrocarbonate freed. The filtrate is made in the same manner as in the above Example is described, worked up further. A crystalline mass is obtained after washing with chloroform and recrystallization from toluene 235 ° melts, easily soluble in ether, acetone and methanol, in ligroin and cyclohexane on the other hand is almost insoluble and has the constitution of 2, 3, 4, 5-tetramethylhydroquinone shows. The yield is 6.5 parts.

From the chloroform solution obtained on washing out, one wins through Concentrate in vacuo 4.5 parts of complex iron compound, which after recrystallization from cyclohexane melts at 133 ° with decomposition.

Example 4 15 parts of iron pentacarbonyl, 34 parts of phenylacetylene, 60 parts of water and 15 parts of ethanolamine are placed under nitrogen pressure of 5 at 40 hours heated in a stirred autoclave to 6o to 7o °. The product is in the example 2 described manner worked up. In addition to 1.8 parts of unchanged phenylacetylene 17.6 parts of a crystalline mass are obtained which melts at 22o to 24o °. the end these are 8.9 parts of 2, 5-diphenylhydroquinone by recrystallization from acetone (Melting point 218 to 21g °), which can be easily found in alcohol and ether, difficult in ligroin, Toluene and cyclohexane dissolves, recovered.

Example 5 = 5 parts of iron pentacarbonyl, 33 parts of butyne-2-diol-1, 4-dimethyl ether, 6o parts of water and 15 parts of ethanolamine are in an autoclave heated with stirring at a nitrogen pressure of 5 at for 24 hours at 70 to 84 °.

After distilling off 5.9 parts of unchanged butynediol dimethyl ether, the product is taken up in methanol, freed from the precipitated ferrocarbonate by filtration and worked up further in the manner described in Example 2. 9.3 parts of 2, 3, 4, 5-tetramethylolhydroquinone-2, 3, 4, 5-tetramethyl ether, which melts at 88 °, are readily soluble in acetone, ligroin, toluene and cyclohexane, and sparingly soluble in water, alcohol and ether are obtained is.

If hexyne-3-diol-2,5-dimethyl ether is used instead of butynediol dimethyl ether, a hydroquinone derivative of the formula is obtained under otherwise identical working conditions which melts at 183 ° and is easily soluble in toluene and cyclohexane, sparingly soluble in ether, acetone and ligroin, and solidly insoluble in water.

Example 6 20 parts of iron pentacarbonyl, 33 parts of i-dimethylaminopropyne-2 and 80 parts of water are in the manner described in Example 2 under nitrogen pressure Heated to 6o to 7o ° for 18 hours.

After 5.5 parts of unchanged dimethylaminopropine have been distilled off, the product is admixed with ligroin and filtered. In the cold, the filtrate gives a crystalline body which, when recrystallized from ligroin, turns into colorless needles with a melting point of 187 °, which are easily soluble in ligroin, toluene and cyclohexane. It has the constitution of a 2,5-bis- (dimethylaminomethyl) -hydroquinone of the formula The yield is 1.8 parts. If, instead of i-dimethylaminopropyne-2, i-diethylaminopropyne-2 is used, the corresponding ethyl compound is obtained with the same procedure with a melting point of 10 °, which is easily soluble in ether, methanol and acetone, but sparingly soluble in toluene, ligroin and cyclohexane.

Example 7 A solution of 100 parts of cobalt carbonyl hydrogen becomes after the addition of 845 parts of 5.3 ° loiger sodium hydroxide solution in a stainless steel pressure vessel under a pressure of 5 atm with a mixture of 2 parts by volume of acetylene and 1 part by volume Nitrogen heated to 100 °.

The product is concentrated by distillation, filtered, with sulfuric acid acidified and extracted with ether. The extract is obtained after evaporation Ether 4.5 parts hydroquinone.

Claims (3)

PATENT CLAIMS: i. Process for the preparation of hydroquinones, characterized in that acetylenic hydrocarbons or their substitution products are allowed to act in the presence of a basic compound with iron or cobalt carbonyls and water or an organic compound which contains one or more hydroxyl groups. 2. The method according to claim i, characterized in that instead of iron or cobalt carbonyls and iron or cobalt compounds included under the Forming reaction conditions carbonyls, used. 3. Modification of the procedure according to claim i, characterized in that instead of iron or cobalt carbonyls their hydrogen compounds, optionally without the addition of a basic compound, used.