Organic compounds -- part of the class 532-570 series – Organic compounds – Oxygen containing
Reexamination Certificate
2000-02-14
2001-05-01
Shippen, Michael L. (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Oxygen containing
Reexamination Certificate
active
06225512
ABSTRACT:
The invention relates to an improved process for the preparation and purification of 3(4-hydroxyphenyl)-1,1,3-trimethylindan-5-ol by isomerisation of dimers or oligomers of isopropenylphenol and subsequent recrystallisation.
There are already several known processes for the preparation of 3-(4-hydroxyphenyl)-1,1,3-trimethylindan-5-ol, referred to below as bisphenol indan.
Thus U.S. Pat. No. 2,754,285 and U.S. Pat. No. 2,819,249 disclose a preparative route via the acid-catalysed dimerisation of &agr;-methylstyrene to indans, which are subsequently sulfonated and then saponified with potassium hydroxide.
U.S. Pat. No. 2,979,534 discloses that the monomeric isopropenylphenols obtained by decomposition of bisphenols can be dimerised to bisphenol indan at temperatures of 110° C. to 160° C. in the presence of aromatic sulfonic acids or mineral acids. Bisphenol decomposition and indan formation can also be carried out in one step. This process yielded a product of low purity, which even after recrystallisation from benzene/cyclohexane had a melting point of only 165-166° C.
U.S. Pat. No. 3,264,357 discloses the preparation of bisphenols by reacting a mixture of the two isomeric forms of dimeric isopropenylphenol with phenols in the presence of strong acids. It is reported that bisphenol indan is formed at a reaction temperature of 90° C. in the absence of reactive phenols. According to U.S. Pat. No. 3,264,358, bisphenol indan can be obtained by reacting a mixture of the two isomeric forms of dimeric isopropenylphenol with strongly acidic catalysts, for example, by heating for two hours in concentrated hydrochloric acid at boiling heat.
U.S. Pat. No. 3,288,864 discloses the preparation of bisphenol indan by self-condensation of monomeric isopropenylphenol at temperatures of 50° C. to 150° C. in the presence of Friedel-Crafts catalysts; JP-A 60/35150 discloses the isomerisation of isopropenylphenol or of its oligomers in the presence of solid catalysts such as aluminium oxide or terra alba.
According to U.S. Pat. No. 4,334,106, bisphenol indan can be prepared by reacting isopropenylphenol or its oligomers in halogenated carboxylic acids or formic acid at temperatures of 0° C. to 90° C.
According to JP-A 5/294879, bisphenol indan can be obtained by thermal decomposition of bisphenol A in the presence of activated clay; U.S. Pat. No. 3,271,463 discloses the formation of bisphenol indan as a secondary product in the treatment of bisphenol A with aqueous sulfric acid at 90° C. to 150° C. In both processes relatively large quantities of spirobisindan bisphenol are formed, and these have to be separated from aromatic hydrocarbons by recrystallisation.
As regards the yields and the purity of the product, the processes described are in many cases still inadequate for an industrial production of bisphenol indan for use as starting material for the production of plastics. An improved process, whereby bisphenol indan can be prepared in high yield and purity, has now been found.
The invention provides a process for the preparation and purification of bisphenol indan, wherein first of all isopropenylphenol, its dimers or oligomers or mixtures of these are dissolved in an organic solvent, the boiling point of which is in the temperature range of 110° C. to 150° C., preferably 130° C. to 140° C., the reaction mixture is heated to a temperature within the range of 60° C. to 110° C., preferably 70° C. to 90° C., then 0.002 to 5 wt. %, preferably 0.3 to 0.5 wt. %, based on the quantity of isopropenylphenol used, of an acidic catalyst is added optionally in portions, the reaction mixture is heated to boiling and allowed to react at the boiling temperature for 1 to 600 minutes, preferably 2 to 60 minutes, then the reaction mixture is optionally neutralised at a temperature within the range of 60° C. to 100° C., preferably 70° C. to 90° C., by addition of a base, then water is added to the reaction mixture and the latter is cooled to a temperature within the range of 0° C. to 30° C., preferably 0° C. to 10° C., the precipitate formed is separated off, dried and recrystallised from an acetic acid/water mixture.
The starting materials used for the process according to the invention are isopropenyl-phenol, its dimers or oligomers. The dimers and oligomers are easily accessible and can be prepared, for example, by the methods described in U.S. Pat. No. 3,288,864 or U.S. Pat. No. 4,201,877.
In the process according to the invention, the solvents used are those organic solvents which have a boiling point in the temperature range of 110° C. to 150° C., preferably 130° C. to 140° C. Examples are toluene, n-butanol, chlorobenzene and xylene; chlorobenzene is preferably used. The quantity of solvent is preferably two to three times the quantity of isopropenylphenol used.
After the reaction mixture has been heated to a temperature within the range of 60° C. to 110° C., preferably 70° C. to 90° C., an acidic catalyst is added thereto in a quantity of 0.002 to 5 wt. %, preferably 0.3 to 0.5 wt. %, based on the quantity of isopropenylphenol used. Bronstedt acids or Lewis acids can be used as catalysts for the process according to the invention. Examples are mineral acids such as hydrochloric acid or sulfuric acid, organic acids such as sulfonic acids or halogenated carboxylic acids, acidic ion-exchange resins, boron trifluoride and metal halides such as AlCl
3
, FeCl
3
or ZnCl
2
. Preferably Lewis acids are used as catalysts, particularly preferably boron trifluoride.
After the addition of the catalyst, the reaction mixture is heated to boiling and allowed to react at boiling temperature for 1 to 600 minutes, preferably 2 to 60 minutes. It has become apparent that, at temperatures within the range of 110° C. to 150° C., in particular 130° C. to 140° C., the isomerisation reaction leads to bisphenol indan with particularly high selectivity.
Optionally the reaction mixture is then neutralised at a temperature within the range of 60° C. to 100° C., preferably 70° C. to 90° C., by addition of a base. A multitude of different bases or mixtures thereof are suitable for this. Examples are metal hydroxides such as NaOH, KOH, Mg(OH)
2
, Ca(OH)
2
, alkoxides such as sodium methoxide, sodium ethoxide, sodium phenoxide, potassium methoxide, potassium ethoxide, potassium phenoxide, magnesium methoxide, magnesium ethoxide, magnesium phenoxide, calcium methoxide, calcium ethoxide, calcium phenoxide, aluminium isopropoxide, carboxylates such as sodium formate, sodium acetate, sodium benzoate, calcium formate, calcium acetate, carbonates such as sodium carbonate, potassium carbonate, calcium carbonate, magnesium carbonate, (NH
4
)CO
3
, hydrogen carbonates such as NaHCO
3
, KHCO
3
or NH
4
HCO
3
, mixtures of NH
4
HCO
3
and ammonium carbamate, ammonia, amines such as triethylaamine, diethylamine, ethylamine, trimethylamine, dimethylamine, methylamine and solutions thereof in water or in organic solvents which are immiscible with the reaction medium. Aqueous sodium hydroxide solution is preferably used as base. If a base which forms a two-phase system with the reaction mixture is used, then after the neutralisation the organic phase containing the bisphenol indan is separated off before further water is added to it.
Water is added to the reaction mixture, which is cooled in order to separate the bisphenol indan. The quantity of water added is preferably one quarter to one third of the quantity of the reaction mixture. The reaction mixture is cooled to a temperature within the range of 0° C. to 30° C., preferably 0° C. to 10° C. The reaction mixture is maintained at this temperature preferably for 1 to 200 minutes, particularly preferably 40 to 80 minutes, before the precipitate formed is separated off This can be effected by the methods known to the person skilled in the art, for example, by filtration, decantation or centrifugation. The precipitate is preferably then washed with an organic solvent, for example, chlorobenzene. It has become apparent that a markedly less coloured product is obtained if the reaction mixture has been ne
Calaminus Wolfgang
Haese Wilfried
Kosik Franz
Westernacher Stefan
Bayer Aktiengesellschaft
Gil Joseph C.
Preis Aron
Shippen Michael L.
LandOfFree
Method for producing and purifying... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for producing and purifying..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for producing and purifying... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2450997