DD159066A1 - PROCESS FOR PREPARING 2.2'-BIS (3.5-DIBROM-4-HYDROXY-PHENYL) -PROPANE - Google Patents

Abstract

The invention relates to a process for the preparation of 2,2'-bis (3,5-dibromo-4-hydroxyphenyl) propane. The 2,2'-bis (3,5-dibromo-4-hydroxyphenyl) -propane is used as a component z. Flameproofing of fibers and plastics suitable. According to the invention, 2,2'-bis (3,5-dibromo-4-hydroxyhpenyl) -propane is prepared by bromination of 2,2'-bis (4-hydroxyphenyl) -propane with elemental bromine in water and hydrocarbon solvents or halogenated hydrocarbon-containing solvent mixtures at 263 to 363 K. of refluxing agents prepared in such a way that the organic layer of the filtrate obtained after filtering off the solids removed from the Bromierungsloesung solid is separated, treated with aqueous bases and, after removal of the aqueous fraction is directly attributed to the bromination.

Description

VEB Leuna-Werke Merseburg, 14 »05®81

"Walter Ulbricht"

8132

Title of the invention

Process for the preparation of 2 _e 2'-bis (3 * 5-dibromo-4-hydroxyphenyl) -propane

Field of application of the invention

The invention relates to a process for the preparation of 2'-2'-bis (3'-5-dibromo-4-hydroxyphenyl) -propane by bromination of 2 _e 2 ^s -bis (4-hydroxyphenyl) -propane. The 2 _e produced according to the invention 2 ^s ~ Bis (3'-5-dibromo-4-hydroxyphenyl) propane is suitable for the grafting of fibers and plastics.

Characteristic of the known technical solutions

It is already known to carry out the bromination of 2 »2'-Βί8 (3.5- <3 ·ίί-bromo-4 ™-hydroxyphenyl) -propane using refluxing solvents «methods which use alcohol-water mixtures as solvents for the bromination , have the disadvantage that, before the solvent is recycled, both the hydrobromic acid contained in the aqueous and in the organic portion of the solvent mixture

It must also be neutralized by alkali (DD-PS 134 515) * This is also the case when working in acetic acid ~ water mixtures as solvent, where it is necessary to neutralize the hydrobromic acid at least partially soluble in the mother liquor Acetate added (DE-OS 2,511,981) ", The above-mentioned methods also have the! Disadvantage _? that the salt formed in the neutralization passes into the reaction solution and there its concentration increases with increasing number of solvent recirculations,

Procedures that the latter !! avoid this, are complicated by the fact that the solvent must be distilled prior to recycling in the bromination (DE-AS 1 268 149) * This laughing part of an energy-consuming distillation dee returning solvent is also vjenn worked in solvent mixtures, the hydrocarbons or halogenated hydrocarbons or containing their mixture and water (DE-AS 1 266 309) »

Object of the invention

It is the object of the invention to develop an economical process for the preparation of 2 * 2 ^t -Bis (3a5 ^ dibromo ~ 4 "aydrophenyl) propane", after which a product of the quality of the comparative method attains _v but whose disadvantageous elaborate processing of the the solvent to be recycled is avoided *

Essence of the invention

It was therefore the task _s to the bromination of 2 _S 2 ^S -Bis (4-hydrophenyl) propane to develop, in which a multiple reuse of the solvent without its elaborate workup is possible "-O a method

According to the invention, this object has been achieved by a process for the preparation of 2 _a 2'-bis (4-hydroxyphenyl) -propane with elemental bromine in Y / asser and hydrocarbons or, containing halogenated hydrocarbon solvent mixtures at 263 to 363 K using return solvent dissolved by the organic layer of ne filtrate obtained after filtering off the pesticide separated from the bromination solution is separated off, treated with aqueous bases, and, after removal of the aqueous portion, is passed directly to the step of 3 ° C ,

As .Ininsatzprodukt for the process according to the invention is technically pure 2 ^ 2 ^! "Bis (4" hydroxyphenyl) propane and technically pure bromine suitable ⁷ The bromination is carried out in solvent mixtures -from a hydrocarbon or halogenated hydrocarbon and water, wherein the mass ratio of the organic solvent component to water 1 to 3 to 3 to 1, preferably 1 to is from 1 to. 1 the bromination temperature should conveniently be lower than 353 K * in general, the reaction solution after completion of the bromine addition to 0 ₅ 5 to 1 hour at 313-333 K he ~ warms "Then cooled the reaction solution to a maximum room temperature and the crystallized 2 * 2 ^? ~ bis (3o5-dibromo-4-hydroxyphenyl) -propane in a known manner, for example by filtration, abs, the filter cake is washed with organic solvent and water or only with water 'to neutrality, and dried * In the filtrate, either before or after washing the filter cake, the organic layer separated Man mixed with bases, vorzugswei sewage has caustic, until partially /? or complete neutralization, after separation of the aqueous fraction, the organic solvent is recycled to the bromine.

According to the procedure according to the invention, a simple, frequent solvent recycling without reduction of the quality of the produced 2e2 ⁱ -Bis (3 "5-dibromo-4-h.ydrosy-

'. '· - 4 - £ J ^ phenyl) propane possible * EXAMPLES Example 1

To a well-stirred mixture of 171 g of 2 '' 2 ^J-bis (4-hydroxyphenyl) propane, 200 ml of methylene chloride and 400 ml Wasser.wurden 480 g of bromine was added so that a reaction was -fcemperatur of 313 K is not exceeded "'after completion of the bromine addition was still Ί h heated under gentle reflux .The reaction solution was cooled to 283 K ^1"' the crystalline 2 ~ * 2 ^ BisC3i'5 dibromo ~ 4 ~ hydroxyphenyl) propane was sucked off "neutral with water washed and air dried. There were 38756 g or 95 % of theory on white 2 * '2 ^? ~ 3us (3a5 ~ dibromo ~ 4 ~ hydroxyphenyl) -propane, with a melting point of 452 to 453 K, and a porosity of 58.9 mass%, was obtained by dissolving the organic layer with 2 g of 10% ^{1 part} by weight of the aqueous IPiltrat layer. sodium hydroxide solution, "separated from the aqueous layer obtained and used in place of unused methylene chloride for the following bromination under the above conditions"'This 395 ₉ 7 g or 97 % of theory of white 2 _a 2' Bis ( 3 -5-dibromo-4-hydroxyphene3-1-propane, having a melting point of 452 to 453 ° C and a bromine content of 58.5% by weight, was recovered by repeated recycling of the organic solvent component (supplementing losses by unused methylene chloride ) in the 18ό ^: Bromierungsansatz 389 _S 6 g or.95j5 % der'Theorie on white 2 ₃ 2 ⁵ -bis (3 * 5-dibr-om-4-hydroxy ~ phenyl5 «propane having a melting point of 451 to 452 K. and a bromine content of 5991 Ma sse percent received »'

Example 2

To a well-stirred mixture of 171 g 2 _S 2 ³ ~ bis (4 · hydroxy ~ phenyl) »propany 150 ml trichlorethylene and 300 ml of water 497 g of bromine was added so that a reaction temperature door of 323 K was not exceeded," Upon completion the bromine addition was heated to 333 K after 0 _{s for} 5 h; Then, the reaction solution was cooled to 283 K; The crystalline 2 «2 ^s ~ propane bis (3, ₉ 5 ~ d i. ~ Bromo-4-hydroxyphenyl) was aspirated, chloroethylene with 100 ml of tri ~ and. then washed neutral with water. "The product was dried at 343 K. * There were 38-1 _r 1 g or 93.5 % of theory on white 2a2 ^? - bis (3e5 ™ dibromo ~ 4 ~ hydroxy ~ phenyl) -propane with a melting point of 449 to 452 K and a bromine content of 59 »0 hasseprozent After separation of the aqueous filtrate layer, the organic layer was added with 4CfSiger natronlauge to neutrality The aqueous layer contained separated and used in place of unused trichlorethylene for the following bromination. After repeated solvent recycling were in 10 * Bromierungsansatz 393.7 or 96.5 % of theory on white 2 * 2 ^s ~ bis (3,5-cLibrom -4 ~ hydroxyphenyl) -propane having a melting point of 451 to 452 K and a bromine content of 58 _S 6 mass%;

Example 3

To a well-stirred mixture of 171 g of 2'-bis (4-hydroxyphenyl) -propane, 150 ml of benzene and 150 ml of water, 480 g of bromine were added so that an Eeact. 333 K was not exceeded ö ^: After completion of the bromine addition, the reaction mixture was cooled to 298 K and the deposited 2i2 * -Bis (3'i5-dibrora-4 ~ bydroxyphenyl) propane was filtered off with suction, the organic layer of the filtrate was separated, with 40% sodium hydroxide solution neutralized and after

Separation of the aqueous layer used for the following bromination batch. The extracted crystals were washed neutral with water and dried in air; There were 363 _? 9 g or 89 _? 2% of theory of white · 2 _β 2'-bis (3e5 ~ dibromo «4-hydroxyphenyl) propane obtained with a melting point of 450J 5-452 K and a bromine content of 58 ₅ 4 mass percent '! Laughing repeated recycling of the organic solvent in the 8 _e bromination mixture 385.5 g or 94 »5 fo of the theory were obtained on white 2'-bis (3i5-dibromo-4-hydroxyphenyl) -propane having a melting point of 450.5 to 451» 5 E and 58p1 Percentage of mass received «

Example 4

To a well-stirred mixture of 171 g of 2 "2 ¹ ~ bis (4 ~ hydro ~ xyphenyl) -> propane, 300 ml toluene and 600 ml of water 490 g of bromine was added so that a temperature of 333 K was not exceeded * ttach terminating the Bromaugabe the temperature was still O ₅ for 5 hours at 333 K gehalten-; Then the reaction mixture to 283 "K was cooled and the precipitated 2 '2 ^s -' Bis (3β 5-dibromo ~ 4-hydro2: yphenyl) propane sucked ₀ The organic layer of the filtrate was separated, neutralized with 40% sodium hydroxide solution and after separating the aqueous layer for the following Bromierungsansatz used β the crystals were extracted with 100 ml of toluene, then washed with water until neutral ^ laughing air drying was 357 g or 87 _S 5% of theory of white 2 * ^t 2 -bis ( 3e'5-dibromo ~ 4 ~ hydrosyphenyl) ~ propane having a melting point of 451 to 452'K and a bromine content of ₅₁ 5 s g ^ Masseprosent laughing repeated recycling of the organic solvent wurden'im 12 _e Broraierungsan rate 389 ₉ 6 g or 95 * 5 % of the theory of white 2 »· 2» -ββ (3 ^ 5-dibromo-4-hydrozyphen7 / l) '- propane having a melting point of 451 to 452 K and a bromine content of 59 _S 1 Masseprosent receiving

Claims (1)

invention claim Process for the preparation of 2 _e 2 '~ bis (3o5 ~ aibromo ~ 4 ~ kyro: xy ~ phenyl) -propane by bromination of 2 _e 2 ^? -Bis (4-hyaroxyphenyl) -propane with elemental bromine in water and containing solvent mixtures of hydrochloric or hydrochloric hydrocarbons * 263 Eis 3o3 K using Rückwärtslösungsmittelj, characterized in that the organic layer of the obtained after aspirating from the Bromiermigslösung deposited Peststoifes Piltratea separated, treated with aqueous bases and returned directly after the removal of the aqueous portion in the stage of bromination «