SU732232A1 - Method of preparing sterically-hindered bis- or polyphenols - Google Patents

Abstract

Sterically hindered bisphenols or polyphenols of the general formula <IMAGE> wherein the substituents are defined in Claim 1, are obtained by reacting sterically hindered 2,4,6-trialkylphenols with acetals or with aldehydes or with cyclic or linear polymers of these aldehydes at a temperature of 60 to 200 DEG C in the presence of an acid catatlyst. The sterically hindered bisphenols or polyphenols may be used, for example, as effective, non-staining, non-toxic and low-volatility stabilisers for natural and synthetic rubbers, plastics and other organic products.

Description

one

The invention relates to the preparation of spatially obstructed bisphenols and polyphenols, in particular, to an improved process for the preparation of bis- or polyphenols of the general formula:

R-CH - R,

T.I1

where Ry and the same silt are different and are / radicgts of the formulas:

ONON

.

is he

where R is a tertiary alkyl C.-Cg,

R. | and RZ are the same or different and

are alkyl C -. or cycloalkyl or | aralkyl, C -, - C, H or alkyl, which are effective neo-staining, non-toxic and low-volatile stabilizers for rubbers, rubbers, plastics and other organic substances. These include the 2.2-methylene-bis- (4-methyl-6-tert-butyl-phenol) widely known and widely used for the stabilization of polymeric materials, sold under the names Antioxidant 2246, KAO-5, Bys-shkofen BP, Agidol-2.

15

. However, despite the great technical value of stabilizers of this type, their production does not develop sufficiently due to the fact that raw materials (4-methylphenol

20 high purity) is a scarce and expensive product.

A known method for producing hindered bis-phenol-2, 2-methylene bis- (4-methyl-625: tert-butylphenol) is the interaction of 2-tert-butyl-4-methylphenol with formchdehyde 1.

There is also known a method for producing some bis-phenols with alkyl

thirty

substituents, for example, a method for preparing 2,2-bis- (4,6-dialkylphenols, in particular 2, 2-methylene-bis- (4-methyl-6-tert-butylphenol) by reacting alkylphenol-4-methyl-2-tert-butylphenol with formaldehyde at 607-80 ° C in the presence of sulfuric acid & catalyst 2.

However, obtaining a whole range of not only bis, but also polyphenols with different values of radicals, including aryl and cycloalkyl, which are effective stabilizers of organic products, is not possible by these methods. In addition, the disadvantages of these methods are the use of 2-tert-butyl-4-methyl-phenol, which has a sharp unpleasant smell, high volatility and toxicity, the formation of large quantities of wastewater during the isolation of the target product, as in the separation of the target product filtering in the filtrate contains gasoline, traces of formaldehyde, methanol, sulfanol, acid, phenol, a large amount of wastewater is also formed when washing the product from acid. In addition, the yield of the product based on the loaded raw material is about 50% of theory.

The purpose of the invention is to increase the yield of the target product, improve sanitary and hygienic working conditions, expand the range of target products and eliminate the formation of wastewater.

To achieve this goal, 2,4,6-trialkyl-phenols of the formula:

where R, K2 have the specified value is subjected to interaction with aldehydes or their donors in an acidic medium, for example, cyclic or linear aldehyde polymers, acetalime formula:

Yaz-0 () g "4

where R and R are the same or different alkyls. The process is carried out at 60-200 C in the presence of an acid type catalyst, for example Lewis acid, Brønsted acid, cation exchange resin in the H-form.

The proposed method allows to obtain bis- or polyphenols from Available Raw Materials with a high yield of 90-98% according to a simple technological scheme. The remaining unreacted raw material can be returned to the reaction without separation and purification. Wastewater is completely excluded, after the reaction, the acid layer (if any) is separated from the reaction mass, and the residual acidity is insignificant and is removed by treatment with anion exchange resin or other known method without formation of wastewater. The resulting n reaction as the splitting off of the t-alkane group of 2,4-dialkylphenol immediately reacts to condensation and does not accumulate in the reaction mass, which significantly improves the working conditions at the facility. The isobutylene that heals during the reaction returns to the process.

Example 1. A reactor equipped with a stirrer, a thermometer and a heating bath was charged with 220 g {1 gmol), 2, b-di-tert-butyl-4-methylphenol, 2.2 g with concentrated sulfuric acid and heated to 120 ° C. temperature of 12Q ° C, 94 g (1.24 g-mol) methylal are fed to the rector for 1.5 hours. At the end of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum, and 143.0 g of 2.2-methylene bis- (4methyl-L-tert-butylphenol) are obtained, which is 97.8% of the theory of reacted 2,6-di-tert-butyl-4-methylphenol, the last conversion 86,0%. After a single crystallization receive the product with so pl. 131-131,. Unreacted 2,6-di-tert-butyl-4-methylphenol and methylal return to the process.

Example 2. 220 g (1 g - mol) 2, b-di-tert-butyl-4-methylphenol, 2.2 g of concentrated sulfuric acid are loaded into the reactor described in example 1, and 76 g (1, 0 g - mol) methylal. The reaction mlss is treated and 12.9 g of 2.2-methylene bis- (4-methyl-b-tert-butylphenol) are obtained, which is 99.1% of the theory for the 2,6-di-tert-butyl reacted 4-methylphenol, last conversion 67.0%. Unreacted methylal and 2,6-day-tert-butyl-4-methylphenol return to the process.

Example 3. In the reactor described in example 1, load 220 g (1 g - mol) of 2,6-di-tert-butyl-4me ylphenol, 2.2 g of sulfuric acid and at 125 ° C for one hour served

14 g (1 G-mol) of acetaldehyde. At the end of the reaction, the catalyst is separated, the volatile products are distilled off in vacuo and 124.6 g of 1.1- (5-methyl-3-ter7 butyl-2-hydroxyphenyl) ethane are obtained, which constitutes 96.4% of the theory for the reacted 2,6-di-tert-butyl-4-methylphenol, the latter conversion is 73%. After a single crystallization, a product is obtained, m.p. 104-104, 5c. Unreacted 2,6-di-tert-butyl-4-methylphenol and acetaldehyde are recycled.

Example 4. In the reactor described in example 1, load 212 g (0.5 g - mol) of 4,4-methylene bis (2, 6-di-tert-butylphenol), 8, 4 g of zinc chloride and at 20 ° C 10 g (0.111 mol) of trioxane is added over 30 minutes. At the end of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum, and 193.7 g of a resin with a molecular weight of 736 (theoretical mb of condensation product 748) are obtained.

Example 5. In the reactor described in example 1, load 170 g (0.5 g - mol) 2,2-methylene bis- (4-methyl-6-tert-butylphenol) 34 g of cation-exchange resin KU-2 (H -form) and at 160 ° C for 1 h serves 8.2 g (0.26 g - mol) paraform (calculated on the 95%). After the end of the reaction, the catalyst was distilled, the volatile products were distilled off under vacuum, and 141.9 g of resin were obtained, containing 46.1% by weight of the condensation product and 53.9% of the starting product.

Example 6. In the reactor described in example 1, load 282 g (1 g - mol) of 2,4,6-tri-tert-butylphenol, 9 g of concentrated sulfuric acid and for 2 hours 110 g (1.17 d - mol) diphenylformal. Upon completion of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum and 120.7 g of 2.2-methylene bis44, 6-ditert-butylphenol are obtained, which is 98.2% of theory, Considering the reacted 2,4,6-tri-tert-butylphenol, the conversion of the latter is 53%. After a single crystallization, a product with mp 141142C is obtained. Unreacted 2,4,6-tritret-butylphenol and dipentylformal return to the process.

Example 7. In the reactor described in example 1, load 155 g (0.5 g - mol) of 2,6-di-tert-butyl-4c. Methylbenzylphenol, 3.2 g of p-toluenesulfonic acid and at 150s for 1.5 hours are fed 21, 9 g (0.255 g - mol of isovaleric gishdehyde. At the end of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum and 120.9 g of 1,1- (6-tert-butyl-4-methylbenzylphenol) isopentane are obtained

iTo accounts for 95.8% of theory, calculated on the 2,6-di-tert-butyl-4-s reaction. -methyl-benzylfe-NOL, conversion of the latter 88%.

Example 8. In the reactor, opi, sleigh in example 1, load 330 g (1.5 g - mol) of 2,6-di-tert-butyl 4-methylphenol, 6.5 g of concentrated sulfuric acid and at 2 hours served 152 g (2 g

Q mol) methyl. At the end of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum, and 200.3 g of 2,6-di- (5-methyl 3-tert-butyl-2-hydroxybenzyl) -n-cresolg are obtained, which is em 87.1% of theory, 5 conversion of 2,6-di-tert-butyl-4-methylphenol 100%. After crystallization, a product is obtained. 163-163.5 ° C.

Example 9. In the reactor described in example 1, load 220 g

0 (1 g - mol) of 2,6-di-tert-butyl-4methylphenol, 11 g of orthophosphoric acid and at 150 ° C. 66 g (1.5 g - mol) of acetaldehyde are fed during 1 h. At the end of the reaction the catalyst are separated, the volatile products are distilled off under vacuum, and 210 g of a mixture of 1,1- (5-methyl-3-tert-butyl-2-hydroxyphenyl) ethane and 2,6-di-5-methyl-3-tert-butyl-2-hydroxy are obtained (methyl) -benzyl) g, P cresol. Conversion of 2,6-di-tert-butyl-4-methylphenol 99%.

Example 10. 123 g (0.5 g-mol) of 2-tert-but-1-6-cyclohexyl-4-methylphenol, 2.2 g of concentrated sulfuric acid are charged to the reactor described in example 1, and heated to 120 ° C , then at 120 ° C for 1.5 hours, 47 g (1.12 gmol) methylal are fed to the reactor. At the end of the reaction, the catalyst is separated,

0, the volatile products are distilled off under vacuum and 163.1 g of 2.2-methylene-bis- (4-methyL7b-cyclogs; xyphenol) are obtained, which is 99.1% of the theory for the reacted 2 (j-tert-butyl) 6-cylohexyl-4-methylphenol, the latter converts to 84%. After the end of crystallization, the product will melt with T. pp. 117-117.5 C. Unreacted 2-tert-butyl-6Q cnclohexyl-4-methyl-fenrl and I methylal return process.

Example. 159 g (0.5 g - mol) of 2,6-di-tert-butyl 4-tert-octylphenol, 2 g of concentrated sulfuric acid are loaded into the reactor described in the example, and 36 g (0, 5 gmol) of aldehyde oil. At the end of the reaction, the catalyst is separated, the volatile products are distilled off under vacuum, and 103.3 g of 1.1- (3-tert-butyl-5-tert-octyl-2-hydroxyphenyl) butane are obtained, which is 95.3% of the theory counting on the 2,6-di-tert-butyl-4-tert-octylphenol which entered into the reaction,

5 last conversion 75.6%. Unreacted 2, b-di-tert-butyl-4 tert-octylphenol and oil aldehyde are recycled.

Example 12. In the reactor described in example 1, load 234 g (1 g - mol) of 2-tert-octyl-4,6-xylenol, 2.4 g of concentrated sulfuric acid and for .1 h served 76 g (1 g - mol) methylal. The reaction mass is processed and 63.5 g of 2,2-methylene bis - (4, b-dimethylphenol) are obtained, which is 81.1% of the theory for the 2-tert-octyl-4 which entered into the reaction, b-xylenol, conversion of the latter 61.2%. Unreacted 2-tert-octyl-4, xylenol and methylal return to the process.

Example 13. In the reactor described in example 1, load 58.5 g (0.25 g mol) of 2.6 di-tert-butyl 4-ethylphenol, I g of concentrated sulfuric acid and at within 30 min served 19 g (0 , 25 g - mol) methylal. The reaction mass is worked up and 26.2 g of 2,2-methylenebis- (4-ethyl-b-tert-butylphenol) are obtained, which is 98.9% of the theory for the 2,6-di-tert-butyl-4- reacted ethylphenol, the conversion of the latter is 57.5%. After a single recrystallization, a product with mp pl.124.5-125 is obtained. Unreacted 2, b-di-tert-butyl-4-ethylphenol and methylal return to the process.

Example 14. In the reactor described in example 1, 141.0 g (0.5 g - mol) of 2-tert-butyl4 methyl - 6-cumylphenol, .1.5 g l of oncentrated sulfuric acid are loaded and at 130 ° C for 1 h served 52 g (0.5 g - mol), ethyl. At the end of the reaction, the catalyst is separated, distilled under vacuum is distilled off. the reaction of 2-tert-butyl-4-methyl-bcumylphenol and ethylal, and 62.5 g of 2,2-methylene bis- (4-methyl-bumumylphenol) are obtained, which is 78.7% of the theory for the 2- tert butyl-4-methyl-6 cumylphenol, the conversion of the latter is 68.5%. Unreacted products are returned to the process.

Example 15. In the reactor described in example 1, load of 70.5 g (0.25 g - mol) of 2-trut-hexyl-4methyl-6-benzylphenol, 20 g of the cation exchange resin KU-2 (H-form) and 17.4 g (0.3 g - mol) of propionaldehyde are fed over 30 minutes. At the end of the reaction, the catalyst was separated, the volatile products were distilled off under vacuum, and 31.4 g of 1.1 (5-methyl-3-benzyl-2-hydroxyphenyl) propane was obtained, which is 91.1% of the theory of the reaction 2-tert-hexyl-4-metsh-gb-benzylphenol, the conversion of the latter is 63.2%. Do not enter

2-tert-hexyl-4-methyl-6benzylphenol and propionaldehyde are recycled to the process

Claims (1)

1. A method for preparing spatial obstructed bis or polyphenols of the general formula: R-CH-R, R. where R and R are the same or different and are radicals of the formulas; 5 HE OH HE R "J HF .K R where R is tertiary alkyl, R and Rj are the same or different and are alkyl, or cycloaclyl, or aralkyl, And or alkyl C — C, o tl and h and y so that, in order to increase output, improving sanitary and hygienic working conditions, expanding the range of target products and eliminating the formation of wastewater, 2,4,6 - triskylphenols formulas: OH he he Rs xCHav R R where R, R and 2. have the above meaning, are reacted with aldehydes Cj by their donors in an acidic medium, for example, cyclic or linear aldehyde polymers, acetals of the formula R3-0 (-CH-0-) nRs R4 where R is the same or different alkyls, at 60-200C in the presence of an acid tkpa catalyst. 2, the method according to claim 1, characterized in that Lewis and Boensted acids are used as the acid type cathode / acid type. cation exchange resins in phosphate. sources of information taken into account in the examination of 73223210 1. USSR Copyright Certificate 97 {n; oto; ip) 245127, cl. C 07 C 37/14, 4036 G ° kG ° 07.7 /,