NL7903553A - High purity bisphenol prodn. in high yield - by reaction of phenol and cpd. contg. ether linkage in presence of acid condensing agent - Google Patents

Abstract

Prodn. of bisphenols comprises reacting, in the presence of an acidic condensing agent, (a) a phenol having a reactive hydrogen para to the phenolic hydroxyl and (b) a cpd. of formula (I), (II), (III) and/or (IV): R and R1 are H, lower alkyl or aryl, X is lower alkoxy or the same as X', Y is Cl or the same as X, X' is aryloxy, n = 3-9, m=n-1, and Z (not defined in the Claims), is 1,2-or 1,3-propylenedioxy (opt. substd. with lower alkyl, lower hydroxyalkyl or hydroxy) or arylenedioxy. The process gives excellent yields of highly pure bisphenols.

Description

* S 2348-951 Ned.

P&C 1

General Electric Company of Schenectady, New York, USA.

Process for the preparation of bisphenols.

The invention relates to the preparation of very pure bisphenols.

It is known that bisphenols, such as bisphenol-A, can be obtained by interacting phenol and acetone or another ketone in the presence of an acidic condensing agent. However, these processes produce products contaminated with a large number of by-products, such as chromanes, spiro compounds, linear or cyclic dinners of isopropenyl phenols and compounds of a more complex structure, which products are generally unsuitable for technical operations without extensive and difficult , time-consuming and energy-consuming purification treatments.

It has now been found that excellent yields of high purity bisphenols can be obtained by replacing the acetone or other ketone as a reactant with a compound having an essential structural characteristic in the arrangement of carbon and oxygen atoms of the formula (1), (2) or (3) of the formula sheet.

It has been found that the reaction proceeds very rapidly near room temperature (about 30 ° C} and that, except for the o.p'-isomer 20 (in the case of phenol as the reactant), only very small amounts of impurities are formed when p.p'- bisphenol-A is the desired product In all cases, the by-products, including the o.p'-isomer, can be easily removed by simply slurrying the separated solid with dichloromethane.

According to the invention, acid catalysis produces a condensation between at least equivalent amounts of a phenol, which preferably contains a reactive hydrogen atom in the para position relative to the phenolic hydroxyl group, and a compound of the formula (41 of the formula sheet, in which each of the symbols R and R '30 represents a hydrogen atom, a (lower) alkyl group or an aryl group, X represents a (lower) alkoxy group or an aryloxy group and Y is a chlorine atom or has one of the meanings given for X .

The condensation is also easily carried out with compounds 7803553 5 η • 1 2 bonds in which R and R 'form part of a common ring, for example in compounds of the formula (5) of the formula sheet, where n is a number with a value of 3 -9 and X and Y have the meanings given above; or with compounds in which X and Y 5 form part of a common ring, for example in compounds of the formula (6) of the formula sheet, wherein Z is a 1,2-propylenedioxy or 1,3-propylenedioxy group (which group contains one or more can bear the following groups: lower alkyl groups, lower hydroxy alkyl groups or hydroxyl) or represents an arylenedioxy group; or 10 with compounds that can be represented by a combination of formulas (5) and (6), as represented in formula (7); or with compounds wherein X or Y represents an unsaturation, such as in formulas (8) and (9), wherein X has the meanings given above and X 'represents an aryloxy group.

Compounds of the general formulas (4) - (9) can be understood as masked carbonyl compounds, which with phenols under acid catalysis give the same products as unmasked carbonyl compounds, but without forming the autocondensation products of the latter compounds, which are responsible for the numerous by-products which occur in the reaction mixture of the reactants with free carbonyl groups. Also, the reactions of the compounds of formulas (4) - (9) with phenols are much faster than those of the conventional carbonyl compounds. The improvements over the conventional condensation methods are evident, inter alia, in the color of the products after removal or neutralization of the acid catalyst: the crude products obtained from the compounds having free carbonyl groups are yellow to orange, while the products which obtained from the masked carbonyl derivatives are white.

The compounds of formulas (4) - (9) can be obtained from carbonyl compounds and alcohols or glycols under acid catalysis; for compounds of formula (4), wherein R 'is a hydrogen atom and Y is chlorine, the acid is hydrochloric acid.

The compounds of formulas (8) and (9) can be prepared by various known methods, the most common of which are the dehydrohalogenation of β-halo ethers and the addition of phenols to acetylene compounds under basic catalysis.

7903553 3 * · * 3 »t

According to a preferred embodiment of the invention, phenol with 2,2-dimethoxypropane of the formula (10) is converted to bisphenol-A.

Particularly preferred compounds of formulas (4) - (9) are those in which X and Y or X 'represent a phenoxy group, since no foreign matter is formed in the reaction mixture when these compounds are reacted with the phenols. . Therefore, the yields are very high and the further processing as well as the recirculation is very simple.

In a preferred aspect, phenol is reacted with isoprope-10-phenyl ether of the formula (11) of the formula sheet to obtain bisphenol-A; and with phenyl vinyl ether to obtain the bisphenol of the formula (12) of the formula sheet.

Although the reaction can generally be carried out at temperatures of about 0 ° -100 ° C, the reaction is usually carried out at temperatures of 15 ° -80 ° C, preferably about 20 ° -65 ° C and in particular at about 30 ° -50 ° C; the reaction can be carried out at atmospheric or superatmospheric pressure.

The reaction can be carried out with or without the presence of solvents, for example dichloromethane, 1,2-dichloroethane, benzene, toluene and the like. A particularly preferred solvent is the reactant phenol itself, which is then used in excess of the stoichiometric amount. The avoidance of foreign solvents greatly simplifies further processing and allows direct recirculation of the phenol.

Any conventional acidic condensing agent may be used, preferably a condensing agent which is soluble in the phenol used, for example hydrochloric acid, brocan hydrochloric acid, mixtures thereof, sulfuric acid or phenol insoluble agents, for example acidic ion exchange resins and the like. When using gaseous hydrochloric acid, superatmospheric pressures provide faster reaction rates.

The condensation reaction can be catalyzed by hydrogen sulfide, mercaptans, thiophenols or compounds with a free 35 -SH group. Solid catalysts, such as the acidic ion exchange resins, can also be modified by terminal sulfhydryl groups.

By "(lower) alkyl group" are meant straight or branched chain carbon chains 7903553 4 hydrogen chains having 1 to about 6 carbon atoms, for example, methyl, ethyl, n-propyl, i-propyl, t-butyl, n-hexyl and the like.

The phenol is used in an at least equivalent amount, for example at least 2 moles, and preferably at least 3 moles, of phenol per mole of the second reactant. For convenience and economic reasons, the phenol is usually used in an amount of 3-12 moles per mole of the second reactant, and the excess phenol can be recovered, usually by distillation, and recycled.

When using a volatile condensing agent, such as HCl, the phenol is melted in practice, after which the condensing agent is added thereto, suitably in an amount sufficient to keep the reaction mixture saturated with the condensing agent; This takes place at a reaction temperature of 15 ° -100 ° C. Superatmospheric pressures are advantageously used. Before or after the addition of the acidic condensing agent, the second reactant can be added in the desired amounts. Condensation is preferably continued until the reaction product typically forms or consists of a slurry of crystals containing the bisphenol in unreacted phenol. The acidic condensing agent can be removed and then the product can be recovered in the usual manner, for example, by filtration, centrifugation and the like. By heating the crystalline material, which is often a complex of the bisphenol with phenol, under reduced pressure, unreacted starting materials are removed, and by-products are removed by washing with phenol or preferably dichloromethane.

For details of the conventional methods of preparing bisphenols using phenol and acetone, reference is made to U.S. Pat. Nos. 1,977,627, 2,623,908, and 3,242,219.

Preferred Embodiments

The invention is further elucidated by means of the non-limiting examples below.

EXAMPLE I

To a melt of 228 g (2.42 7903553 ir% 5 mol) of phenol saturated with hydrogen chloride, a solution of 31.2 g (0.3 mol) of 2,2-dimethoxypropane in 30 ml of dichloromethane was added dropwise at 40.5 ° C. added; the 2,2-dimethoxypropane can be prepared by reacting acetone and methanol in a continuous process and using catalysis with sulfonated polystyrene. After about 2/3 of the solution was added, the color of the mixture changed to orange. The whole solution was added in 1 hour, and after the mixture was kept at 35 ° C-39 ° C for an additional 2 hours, the bisphenol A adduct precipitated. The reaction mixture was filtered and freed from volatile material in a rotary evaporator. The white solid residue was washed with dichloromethane and the residue was freed from volatile material. According to gas chromatographic analysis, the product fractions had the following total composition:

Compound Retention time (min.) Composition (mol%) 15 2,4'-isopropylidene diphenol 16.52 0.8 (o.p'-BFA) "Chroman-I" 1) 17.57 5.3 4.4'- isopropylidene diphenol 17.93 93.0 (p.p'-BFA) 24.92-25.59 1.2 20 Higher diene phenols 14.01 p.cumylphenol (reference) 1) "Chroman-I" has the structure of formula (13) of the formula sheet.

The filtered solid, once washed with dichloromethane, contained 99.7 mol% p.p'-BFA, 0.19 mol% o.p'-BFA and 0.04 mol% higher molecular weight products.

EXAMPLE II

The procedure of Example 1 was repeated, except that an equivalent amount of acetone (17.4 g, 0.3 mol) was used instead of 2,2-dimethoxypropane. The course of the reaction was followed by gas chromatography, showing the following changes in the composition:

Compound Composition (mol%)

After 1 hour After 5 hours After 23 hours o. P'-BFA 29.1 17.3 8.0 35 "Chroman-I" 1) 0.0 0.4 0.5 p. P'-BFA 67.6 80.1 90.1

Higher di- and triphenols 3,3 2,2 1,4 1) "Chroman-I" has the structure of formula (13) of the formula sheet.

7903553 4 ^ 6

EXAMPLE III

In a solution of 697 g (5.9 mol) diethyl acetal and 3764 g (40 mol) phenol, a slow flow of anhydrous hydrogen chloride gas was introduced at 40 ° C with stirring. External cooling was used to keep the reaction temperature between 36 ° C and 48 ° C. After 2.5 hours, solid began to separate from the solution, at this point the introduction of HCl was stopped and allowed to run. crystallize the reaction mixture at ambient temperature for 12 hours.

The solid, which was filtered, washed with cyclohexane and air dried, weighed 890 g and consisted of the 1: 1 adduct of 4,4'-ethylidene diphenyl and phenol. After separation of the phenol by distillation under reduced pressure at 14 mmHg, the diphenol remained, which, according to gas chromatographic analysis, had a purity of 98.3%.

15 Compound Retention time (min.) Composition (mol%) 4,4'-ethylidene diphenol 17.32 98.3 2.4'-ethylidene diphenol 16.32 1.7 p.cumylphenol (reference) 13.83

Recrystallization from benzene gave 4,4'-ethylidene-20 diphenol, m.p. 123 DEG-125 DEG C., which, according to gas chromatography, had a purity of 99.8%.

EXAMPLE IV

The procedure of Example 3 was repeated, except that 780 g of propion-aldehyde-diethylacetal were used instead of diethyl acetal. At the end of the reaction, before solid separation (while the reaction mixture was still warm), gas chromatographic analysis revealed the presence of 91.5% diphenols and 8.5% higher molecular weight products.

The mixture of diphenols had the following composition: Compound Retention time (min.) Composition (mol%) 2,2'-propylidene diphenol 15.79 5.2 2.4, propylidene diphenol 16.74 28.0 4.4'- propylidene diphenol 17.96 66.8 p-cumylphenol (reference) 13.97 After removal of the alcohol under reduced pressure, the liquid reaction mixture remained, from which the phenol adduct of 4,4'-propylidene diphenol was soon deposited. Filtration and recrystallization of the white filtrate from benzene gave 99.9% pure 4,4'-propylidene diphenol, mp 131-132 ° C.

EXAMPLE V

The procedure of Example IV was repeated, however with the difference that 342.7 g of propionaldehyde were used instead of propionaldehyde-diethylacetal. Gas chromatographic analysis at the end of the reaction revealed the presence of 87.2% diphenols of the following composition:

Compound Retention time (min.) Composition (mol%) 10 2,2'-propylidene diphenol 15,55 13,0 2,4'-propylidene diphenol 16.59 27.9 4,4'-propylidene diphenol 17.83 60.2 p. cumylphenol (reference) 13.82

EXAMPLE VI

The procedure of Example IV was repeated, except that one mole of propionaldehyde diethyl acetate was used and the phenol was replaced by the equivalent amount of o.cresol (1081 g, 10 mol). Gas chromatographic analysis showed the following composition for the diphenols at the end of the reaction: Compound "Retention time (min.) Composition (mol%) 6,6'-propylidenedio-o.cresol 18.21 1.5 4.6 ' -propylidene di-o.cresol 18.43 13.9 4,4'-propylidene di-o.cresol 19,19 84,6 p.cumylphenol (reference) 14,13 25 A small amount (approx. 2.8%) of a higher molecular weight product was also formed in the reaction (retention time: 26.47 min.).

EXAMPLE VII

The procedure of Example 6 was repeated, except that the propionaldehyde diacetal was replaced with 1 mol of 1,2-isopropylidene glycerol. The crude reaction mixture had the following composition:

Compound Retention time (min.) Composition (mo 1%) 4.6, -isopropylidene di-o.cresol 18.12 9.0 35 4.4 * -isopropylidene di-o.cresol 19.90 91.0 p.cumylphenol (reference 15.67 7903553

• .1 I

8

EXAMPLE VIII

The procedure of Example 6 was repeated, except that the propionaldehyde-diethyl acetal was replaced by the equivalent amount of 1,1-dimethoxycyclohexane (144.2 g, 1 mol), boiling point 54 ° C at a pressure of 15 mmHg. Gas chromatographic analysis showed the composition below at the end of the reaction:

Compound Retention time (min.) Composition (mol%) 4.41-cyclohexylidene diphenol 23.35 98.7 2,4'-cyclohexylidene diphenol 21.85 1.3 10 p.cumylphenol 15.68

Recrystallization from aqueous methanol gave 99.8% pure 4,4 * diphenol, mp 188 ° -189 ° C.

EXAMPLE IX

The procedure of Example VIII was repeated, except that the 1,1-dimethoxycyclohexane was replaced by the cyclic acetal of 1,2-propanediol and cycloheptanone. Gas chromatographic analysis shows that the reaction product had the following composition:

Compound Retention time (min.) Composition (mol%) 20 4,4'-cycloheptylidenediphenol 25.35 97.8 2.41-cycloheptylidenediphenol 23.02 2.2 p.cumylphenol (reference) 16.47

Recrystallization from aqueous methanol gave the 4,4'-cycloheptylidenediphenol in a purity of 99.1%; the melting point was 208 ° -209 ° C.

EXAMPLE X

The procedure of Example I was repeated, except that the 2,2-dimethoxypropane was replaced with 45.0 g (0.3 mol)

2-phenoxypropylene (which can be prepared from phenol and propyne with potassium hydroxide or from sodium phenate and 1,2-dichloropropane). After the end of the reaction, gas chromatographic analysis revealed the presence of only p.p'-BFA (94.6%), o.p'-BFA (5.4%) and excess phenol. EXAMPLE XI

The procedure of Example IV was repeated, except that the propionaldehyde diethyl acetal was replaced by 122.6 g (1.0 mol) of a-chloropropylethyl ether (which compound can be readily obtained from propionaldehyde, ethanol and anhydrous chlorine 7903553

Claims (11)

Process for the preparation of bisphenols, characterized in that a phenol with a reactive hydrogen atom in the para position relative to the phenolic hydroxyl group is reacted with the compound of the formula (4) in the presence of an acidic condensing agent. 5), (6), (7), 30 (8) or (9) wherein each of the symbols A R 'represents a hydrogen atom, a lower alkyl group or an aryl group, X represents a lower alkoxy group or has the same meaning as X *, Y is a chlorine atom or has one of the meanings given for X, X 'is an aryloxy group, Z is a 1,2- or 1,3-propylenediaxy group (which can optionally contain one or more hydroxy groups, lower alkyl groups or low hydroxyalkyl groups as substituents) or) represents an arylenedioxy group, n is a 7903553 number having a value of 3-9 and m = (n-1), or a mixture of these compounds. 2. Process according to claim 1, characterized in that phenol is reacted with 2,2-dimethoxypropane to obtain bisphenol-A. Process according to claim 1, characterized in that phenol is reacted with isopropenylphenyl ether to obtain bisphenol-A. Process according to claim 1, characterized in that phenol is reacted with acetal to obtain 4,4'-ethylidene diphenolo 5. Process according to claims 1-4, characterized in that the reaction temperature is kept in the range of about 20 ° -65 ° C. The procedure of Example X was repeated, except that the 2-phenoxypropane was replaced by 36.0 µm (0.3 mol) phenyl vinyl ether. At the end of the reaction, gas chromatographic analysis revealed the following composition: Compound Retention time (min.) Composition (mol%) 10 4,4'-ethylidene diphenol 17.38 98.6 2,4'-ethylidene diphenol 16.37 1.4 p. cumylphenol (reference) 13.90 EXAMPLE XIXX The procedure of example IV was repeated, except that instead of propionaldehyde-diethyl acetal, 214.3 g (1 mol) of acetaldehyde-diphenyl acetal was used (the latter compound being obtained from phenyl vinyl ether and acetic acid by disproportionation). In this very good reaction, 4,4'-ethylidene diphenol (97.6%) and 2.4 * ethylidene diphenol (2.4%) were the only products present in the adduct. The invention is not limited by the above-described embodiments, since numerous modifications are of course possible within the scope of the invention. 25 CONCLUSIONS: 6. Process according to claims 1-5r, characterized in that hydrogen chloride is used as the acid condensing agent. 7. Process according to claims 1-6, characterized in that the bisphenol-phenol adduct is separated in solid form and the solid product is washed with dichloromethane until practically free of by-products. Process according to claim 2, characterized in that phenol and 2,2-dimethoxypropane are reacted in the presence of hydrogen chloride at a temperature of about 20 ° -50 ° C, to obtain bisphenol-A. 9. Process according to claim 8, characterized in that the bisphenol-20 A in solid form as the adduct with phenol is separated from the reaction mixture and the solid product is washed with dichloromethane until practically free of by-products. 10. Process according to claim 3, characterized in that phenol and isopropenylphenyl ether are reacted in the presence of hydrogen chloride at a temperature of about 30 ° -50 ° C to obtain bisphenol-A. Process according to claim 10, characterized in that the bisphenol-A in solid form as the adduct with phenol is separated from the reaction mixture and the solid product is washed with dichloromethane until practically free of by-products. 7903553