FI81779C - META-OCH PARA-ISOPROPENYL -, -DIMETHYL-BENZYLAMINE. - Google Patents

Description

1 81779

This invention relates to isopropenylbenzylamine compounds from which polymers can be used in sizing paper.

U.S. Patent 4,439,616, issued March 27, 1984, describes a process for the preparation of tertiary aralkyl isocyanates, e.g. Such a process is particularly useful in the preparation of meta- and para-isomers of TMXDI, with significant amounts of the corresponding meta-isopropenyl α, α-dimethylbenzyl isocyanate (m-TMI) and para-isopropenyl-α as by-products, α-dimethylbenzyl isocyanate (p-TMI).

In such systems, the by-product m-TMI or p-TMI can be recycled to the process to improve the overall yield of TMXDI, but as such has significant use as a separate product due to its difunctional nature or the reactive isocyanato (-NCO) and isopropyl groups.

This invention relates to TMI-derived meta- or para-isopropenyl-α, α-dimethylbenzylamines of formula (I).

35 I

2,81779 and salts of these compounds of formula

N «2 * A

wherein A is a mineral acid or a carboxylic acid.

The invention also relates to a process for the preparation of meta- or para-isopropenyl-α, α-dimethylbenzylamine; this process is characterized in that a) the corresponding meta- or para-isomer 15 (m-TMI or p-TMI) of isopropenyl α, α-dimethylbenzyl isocyanate (TMI) is hydrolyzed in the presence of hydrochloric acid or sulfuric acid, isopropenyl α, a -dimethylbenzylamine hydrochloride, and b) reacting isopropenyl-α, α-dimethylbenzylamine hydrochloride with a stoichiometric excess of sodium hydroxide to isopropenyl-α, α-dimethylbenzylamine.

The invention further relates to an alternative process for the preparation of meta-isopropenyl-α, α-dimethylbenzylamine; this method is characterized in that a) a first solution consisting of a methanolic solution of m-isoprepenyl-α, α-dimethylbenzyl isocyanate is heated for a sufficient time to methyl N- (3-isopropenyl-α, α-dimethylbenzyl) carbamate (TMU); ), b) mixing a first solution containing methyl N- (3-isopropenyl-α, α-dimethylbenzyl) carbamate (TMU) and potassium hydroxide and 2-methoxyethanol to form a second solution, c) heating said second solution at a sufficient temperature to for a long time that said TMU is converted to m-isopropenyl-α, α-dimethylbenzylamine, and

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3 81779 d) isolating m-isopropenyl-α, α-dimethylbenzylamine from said second solution.

In step b) above, potassium hydroxide is used to such an extent that the molar ratio of TMU to potassium hydroxide is about 5 about 0.25 ... n. 0.50.

Polymerization products of the above compounds include poly- (m-isopropenyl-α, α-dimethylbenzylamine), poly- (p-isopropenyl-α, α-dimethylbenzylamine) and copolymers formed from m- or p-isopropenyl-10-li-o , α-dimethylbenzylamine and at least one unsaturated comonomer polymerizable therewith.

m-Isopropenyl-α, α-dimethylbenzylamine and p-isopropenyl-α, α-dimethylbenzylamine (hereinafter abbreviated as m-TMA and p-TMA, respectively) are novel compounds which can be polymerized into dimeric or oligomeric cationic products and which are mixed poly -measurable with other ethylenically unsaturated comonomers as copolymers; m-TMA and p-TMA are also homopolymerizable to high molecular weight products.

Meta- and para-TMA and the polymer products formed therefrom, as well as their acid salts, can be used in paper sizing, as flocculants, and in the preparation of water-soluble cationic polymers, with the final applications being water clarification and hair sprays.

p-TMI, prepared e.g. by the method described in the aforementioned U.S. Patent 4,439,616, readily reacts to hydrochloride salt of p-TMA in a reaction mixture containing p-TMI, dilute aqueous hydrochloric acid and acetone. This reaction mixture can be reacted at room temperature with stirring to form a fine suspension of the reaction product. Acetone can be evaporated from the reaction product and the remaining reaction product is filtered to give isopropenyl-35α, α-dimethylbenzylamine hydrochloride (TMA.HCl) as an impure acid salt. From this, TMA.HC1 can be isolated, e.g. by recrystallization from water. The free base (TMA) can then be obtained by mixing the acid salt and a stoichiometric excess of a strong base, e.g. sodium hydroxide, and extracting the resulting reaction product with TMA as a suitable solvent such as hexane.

Although the acid salts and pure compounds of TMA can be prepared as described above, in practice it is advisable to use this procedure to prepare the para-acid-10 salt and the pure compound. An alternative method that is highly efficient for the preparation of both isomers is the preferred method for the preparation of meta-isomers of the TMA acid salt and pure TMA.

In an alternative method, TMU can be prepared, e.g., by heating a methanolic solution of TMI, e.g., for 6 to about 20 hours, at reflux without any catalyst. Alternatively, TMU can be prepared in U.S. Patent Application Serial No. 457,083, filed 10.1. 1983, B. Singh et al., According to which tertiary N-20 aralkylurethane esters are prepared by reacting carbamic acid esters of an alkyl or aralkyl alcohol with a tertiary aralkyl diol. If the Stoichiometric amount of carbamate is limited in this reaction system, the diol is selectively converted to monourethane.

The TMU-containing solution can then be hydrolyzed by heating in the presence of a base such as potassium hydroxide in an alcoholic solvent such as 2-methoxyethanol at the boiling point of the solvent for about 1 to about 3 hours. The boiling solution is then cooled and stirred with methylene chloride to give a solution from which 2-methoxyethanol is extracted by treatment several times with water. The methylene chloride containing the product TMA can then be dried, e.g., with a molecular sieve or anhydrous potassium carbonate, and distilled to recover the TMA.

li 5 81779

Homopolymers or copolymers of meta and para-TMA according to the invention consisting of meta and para-TMA or one of them and other ethylene comonomers such as styrene, methylstyrene-5, p-methylstyrene, p-methyl -methylstyrene, alkene hydrocarbons having 2 to 8 carbon atoms, halogenated alkenes, acrylic or methacrylic monomers and the like can be successfully used as paper sizing agents. Acid salts of TMA homopolymers and copolymers are also useful in paper sizing.

The preparation and use of the above-mentioned polymers for gluing paper is described in more detail in Finnish patent application 842188 (publication 80281).

U.S. Patent No. 4,369,292 discloses organic pigments that can be used as paper fillers. These pigments consist of a graft copolymer of an ethylenically unsaturated monomer and a cationic prepolymer. The structural component of said prepolymer is a vinyl or isopropenylbenzylammonium salt which may be further N-substituted by 1 to 3 organic groups. The publication does not mention the use of pigments for gluing paper.

The following examples illustrate the invention. In the examples, all parts and percentages are by weight unless otherwise indicated.

Example 1

When 40 g of p-TMI and 75 cm 3 of 4-N hydrochloric acid were mixed at room temperature, no detectable reaction took place. 75 cm3 of acetone were then added to make the mixture more uniform and the mixture was stirred overnight. During this time, the upper liquid phase disappeared and a fine suspension formed. Filtration gave 9.0 g of crude p-TMA.HCl, m.p. mp 220 ° C. After most of the acetone had evaporated from the filtrate, a further 22 g of 6 81779 products were obtained, m.p. 216-218 ° C. Recrystallization from water or acetonitrile gave the product with a melting point of 223-225 ° C and a yield of about 80%. The mother liquors contained a significant amount of N, N'-bis- (4-isopropenyl) -α, α-dimethyl-5-benzylurea.

Example 2

9.5 g of p-TMA.HCl are added to 40 cm3 of concentrated sulfuric acid. During the slightly exothermic reaction, a deep red color developed and hydrogen chloride evolved. The reaction mixture was then heated on a water bath for 1 h, poured onto ice, basified with sodium hydroxide and extracted with CH 2 Cl 2. The extract was dried over solid H 2 O and evaporated. Upon dilution of the syrupy residue with hexane, a small amount of solid separated which turned out to be the aromatic sulfonate salt. Evaporation of the hexane solution gave 7.3 g of a syrupy substance as a residue. The infrared spectrum of this product did not change significantly after distillation; the boiling point was about 195 ° C / 0.5 mm. The NMR spectrum showed the indane di-20 mer TMA structure shown below. The mass spectrum confirmed the empirical formula and the area% on chromatography was 97.9.

Example 3

Indanediamine 1- [4- (1-amino-1-methylethyl) phenyl] -6- (1-amino-1-methylethyl) -1,3,3-trimethylindan-25-m 2 m2 —Nh2 from Example 2 was also prepared by hydrolysis / dimerization of p-TMI in 70% sulfuric acid in one step. 10 g of 35 p-TMI in 10 cm 3 of toluene were added dropwise to 98 g of 7,81779 70% sulfuric acid preheated to 60 ± 5 ° C. After the evolution of carbon dioxide ceased, the mixture was heated at 80 ° C for 90 minutes. The mixture was then cooled and poured onto ice. The diamine sulfate crystallized out, which was isolated by filtration and dried as well as possible by suction. Analysis of the cold filtrate formed by toluene and dilute sulfuric acid revealed that it was substantially free of dissolved amine salt. The isolated amine salt (soluble in acetone or water) was dissolved in water and basified with NaOH. The precipitated gum was extracted with CH 2 Cl 2, the extract was dried over potassium carbonate and the product was isolated by evaporation of the solvent. The infrared spectrum showed that this product was the same as the diamine prepared in Example 2 using p-TMI.HCl as starting material.

Example 4

Unlike p-TMA, the meta-isomer of TMA could not be satisfactorily prepared by hydrolysis of m-TMI with hydrochloric acid because linear oligomeric products tend to predominate in the reaction product.

Therefore, m-TMA was prepared by hydrolyzing methyl N- (3-isopropenyl-α, α-dimethylbenzylcarbamate (m-TMU) with a base as follows: 25 yn .NHC00CH ·.

foTp - ^ - + (oy + CH 3 OH

methoxyethanol + K2CO3

ra-TMU m-TMA

30 m-TMU was prepared by refluxing a methanolic solution of m-TMI overnight without catalyst. The boiling point of the pure compound was 126 ° C / 0.5 mm. It was a highly viscous liquid that eventually crystallized at room temperature when stabilized with tert-butyl catechol.

β 81779

Without a catalyst, m-TMI polymerizes slowly at room temperature, e.g., 20% per month at ambient conditions.

A solution of 250 g of 91%, about 1.0 mol) of m-TMU and 165 g (2.5 mol) of 85% KOH in 460 cm 3 of 2-methoxy-5 ethanol was boiled. 2.5 hours. The solution is then cooled and mixed with 500 cm3 of water and 700 cm3 of CH2Cl2. The amine-containing CH2Cl2 phase was separated and washed several times with 500 cm3 portions of water until the volume of the phase remained constant. In this way, the remaining 10 2-methoxyethanol was removed. The CH2Cl2 solution was then dried over potassium carbonate and distilled. The obtained m-TMA was 93% pure and had a boiling point of 106 ° C / 2 mm. The yield was 128 g, 73% of theory. Capillary GLC revealed an inseparable by-product that could indicate a 2% yield of p-TMA. Approximately 4-5% of unchanged m-TMU was recovered as an indication that it might have been advantageous to continue the hydrolysis a little further.

The two by-products found in the higher boiling fractions turned out to be m-TMXDA from a small amount of m-TMXDU in the starting material and to the transesterified urethane: ^ \ VNHCOOCH2 CH2OCH 3 f which could have been converted to m-TMA by prolonged hydrolysis.

Example 5 1- [3- (1-Amino-1-methylethyl) phenyl] -5- (1-amino-1-methylethyl) -1,3,3-trimethylindan

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981779 NH-> 5 nh2 was prepared by dimerization of m-TMA according to the method described above. Several oligomerization experiments with m-TMA 10 showed that a relatively dilute acid (e.g. 37% HCl) gave only linear oligomers and a more concentrated acid (e.g. 85% H 2 SO 4) formed cyclizable (indan) at room temperature. ) dimer.

A solution of 28.9 g of m-TMA (93%, ca. 170 eq. 15 bases) in 150 cm 3 of hexane was cooled on ice and treated dropwise with 8 cm 3 of 18 N sulfuric acid while stirring vigorously. . A reddish purple color immediately formed and the reaction was slightly exothermic, but the temperature was maintained at 20-30 ° C by cooling in an ice bath. The amine salt sootically dissolved in the viscous acid phase. After 15 minutes, the reaction mixture was briefly warmed to 50 ° C to complete the reaction. The bright color then turned wax brown. After adding 200 g of ice, the mixture was basified with more than 25% concentrated NaOH solution and the hexane phase was isolated. The phase was dried over solid potassium carbonate, evaporated to 19.2 g of syrup and GLC analyzed. According to the analysis, the purity was 90% by weight and the impurities were less than 5% by area. The IR spectrum showed only structure. A small amount of the hexane-insoluble gum in the reaction mixture was largely dissolved as the extraction was continued with CH2Cl2, leaving a small amount of fluffy, insoluble material. An additional 8.6 g of syrup was obtained from the CH 2 Cl 2 extraction, of which 72% by weight was dimer, cyclic indan, but which also contained a significant amount of 10 81 779 significantly less volatile higher oligomers and a small amount of linear dimers. The total yield of cyclized indan dimer was about 86% based on the actual m-TMA starting material (GLC analysis).

5 Example 6

In a larger scale run performed as in Example 5, but using toluene instead of hexane, side alkylation of the solvent became a serious drawback: 10 CH 3 ♦ (cp n "2 NH 2 - 2- (m- (1-amino-1-methylethyl) phenyl) -2-p-tolyylipr ° Paani

Distillation of the crude product from 78 g of m-TMA gave 71% of the above alkylation product in several fractions. About 10% of the product was essentially non-volatile polyamine. Separation of m-indanediamine by fractionation from the less volatile diamine was not possible due to the very high boiling points of these compounds. The fraction boiling at 172-181 ° C (125 mm) contained 36% monoamine and 61% cyclic indan dimer. In the best product, kp. 186 ° C / 1 mm, was 96.8 area% m-indanediamine, 0.4 area% monoamine and 1% of each of the three slightly higher boiling by-products.

According to the analysis, this substance contained 5.74 meq. N H 2 / g, calculated value 5.71. At room temperature the substance was a very viscous syrup.

Successful dimerization of m-TMA in concentrated sulfuric acid initially required conversion to the amine salt 35 (either hydrochloride or sulfate) in a more dilute acidic acid.

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11 81779 sa at low temperature to avoid a violent paid reaction. It is recommended that the amine salt be then added to concentrated sulfuric acid (e.g., 85%) to minimize the formation of higher oligomers in the dilute acid.

Example 7

The monoamine mentioned in Example 6 was also prepared from m-TMI as follows.

A mixture of 200 cm 3 of 36 N sulfuric acid and 100 cm 3 of 10 heptane was preheated to 65 ° C and a solution of 252 g (1.24 mol) of m-TMI in 250 cm 3 was gradually added over 2 hours. heptane. The reaction temperature was maintained at 70-80 ° C with slight heating and the addition rate was adjusted so that the evolution of carbon dioxide continued to be strong. At this point, the reaction mixture was a viscous, red-purple syrup. After the evolution of carbon dioxide ceased, the mixture was allowed to cool and then basified (at 50-60 ° C) by the careful addition of 8 moles of concentrated aqueous sodium hydroxide solution. The heptane phase was then separated and the aqueous phase was re-extracted with a small amount of heptane. The combined heptane solutions were dried over solid potassium carbonate, evaporated to give 219.5 g (theoretical 217 g) of crude amine.

The crude indanediamine was distilled on a simple Vigreaux apparatus to give 154 g, b.p. about 165 ° C / 5 mm, according to GLC purity about 97 area% (yield 71%). Approximately 23 g (11% yield) of a much higher boiling agent was also obtained, presumably a trimer mixture of at least four major components (GLC analysis), b.p. 220-230 ° C / 0.5 mm, amine equivalent weight 207 (theoretical 175). 13 C-NMR showed an indane structure in this fraction of about one indan unit per four phenyl groups. In addition, less than 35 volatile products were obtained as a distillation residue. According to chromatography, the two smaller 12 81 779 components were apparently identical to the linear dimers obtained in Example 8 in 12-n HCl.

Example 8

Attempts to hydrolyze m-TMl to m-TMA.HCl using 5 N HCl in acetone (25 ° C) or toluene (65 ° C) did not result in a crystalline salt such as the p-isomer. The hydrochloride remaining dissolved in the acid solution or in the aqueous phase apparently oligomerized to some extent. In the 12-n HCl / acetone system described above, about 15% of m-TMA was recovered by basification after about twenty hours at room temperature. Another 15% of TMI was converted to 1- (1-amino-1-methylethyl) -3- (1-hydroxy-1-methylethyl) benzene in nh 2 20 kp. 150 ° C / 1 mm, m.p. 86 ° C. GLC analysis of the non-distilled higher boiling residue showed no indanediamine of the type described in Example 5.

The 12-N HCl / toluene system at 65 ° C (90 minutes) gave small amounts of m-TMA and hydroxyamine and 25 traces of p-TMA.HCl. About half of the base formed distilled at 230-380 ° C / l mm, and was apparently a mixture of the same linear dimers and trimers obtained at a lower temperature. 13C-NMR could not show the indane structure.

30

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Claims (3)

1. Meta or para-isopropenyl-α, α-dimethylbenzylamine of formula (I) N Process for the preparation of the meta- or para-isopropenyl-α, α-dimethylbenzylamine according to claim 1, characterized in that a) the corresponding meta- or para-isomer isomer of iso-propenyl-α, in the presence of hydrochloric or sulfuric acid to isopropenyl-α, α-dimethylbenzylamine salt, and b) the resulting isopropenyl-α, α-dimethylbenzylamine salt is reacted with a stoichiometric excess of sodium hydroxide to isopropenyl-α-isopropenyl-α the snake 1. 25 Process for the preparation of the meta- or para-isopropenyl-α, α-dimethylbenzylamine according to claim 1, characterized in that a) a first solution consisting of m-isopropenyl-α, α-dimethylbenzyl isocyanate dissolved in methanol is heated. B) the first solution containing methyl N- (3-isopropenyl-α, α-dimethylbenzyl) carbamate, and sufficient time to form methyl N- (3-isopropenyl-α, α-dimethylbenzyl) carbamate; potassium hydroxide and 2-methoxyethanol are mixed to form a second solution, ie 81779 c) the said second solution is heated at a sufficient temperature so long that methyl-N- (3-isopropenyl-α, α-dimethylbenzyl) the carbamate is converted to m-isopropenyl-α, α-dimethylbenzylamine, and d) m-isopropenyl-α, α-dimethylbenzylamine is isolated from said second solution.