PL230028B1 - New ammonium ionic liquids, containing [2-(methacryloyloxy)ethyl]-trimethylammonium cation and organic anion, method for obtaining them and application as cellulose solvent - Google Patents

Description

Description of the invention

The subject of the invention is new ammonium ionic liquids containing the [2- (methacryloyloxy) ethyl] trimethylammonium cation and an organic anion, the method of their preparation and the use as a cellulose solvent.

Ionic liquids are organic compounds with an ionic structure, the characteristic feature of which is the melting point lower than 100 ° C. The advantages of the ionic structure and the liquid state of the aggregate in combination with the significant possibilities of designing the structures of organic cationic and anionic groups determine the wide variability of the properties of individual compounds from this group and high application potential. In general, ionic liquids are characterized by high thermal stability, good electrical conductivity and a non-measurable vapor pressure under normal conditions. This property effectively reduces the uncontrolled emission of ionic liquids to the environment and makes them a "green" alternative to traditional, often toxic and easily flammable organic solvents.

The physicochemical properties of ionic liquids, which depend on both the properties of the cation and the anion, can be easily modified by, for example, carrying out an anion exchange reaction with a structure containing previously designed chemical moieties. A huge number of possible combinations of cation-anion of the ionic liquid, reaching an estimated 10 ^18, makes the above-described physicochemical changes can be readily predicted.

[2- (Methacryloyloxy) ethyl] trimethyl ammonium chloride is obtained by quaternizing 2- (dimethylamino) ethyl acrylate or methacrylate with methyl chloride. This salt is used as a monomer from which a water-soluble cationic polymer called polyquaternium 37 is obtained by polymerization of the methacrylate moiety. It is used as an anti-electrostatic and film-forming agent in hair care cosmetics. Chloride copolymers are also used as agents in industrial processes, e.g. as flocculants in water treatment processes. On the other hand, unpolymerized [2- (methacryloyloxy) ethyl] trimethylammonium chloride exhibits fungicidal properties. Salts having an organic anion and [2- (methacryloyloxy) ethyl] trimethylammonium cation are described in the literature (W. Zhou, KQ. Ma, LH. Tang, F. Li, L. Huang, JH. Chen, J. Appl. Polym. Sci., 2014, 131, 41002). Hydrophobic compounds with this cation may find use in the preparation of polymeric materials with high water resistance as reported in Cardiano, P., Mineo, P.G., Neri, F., Lo Schiavo, S., Piraino, P., J. Mater. Chem., 2008, 18, 1253-1260.

Replacing the chloride anion with the herbicide anion allows to obtain phytotoxic ionic liquids. Salts containing [2- (methacryloyloxy) ethyl] trimethylammonium cation and an organic anion derived from herbicidal acid, which is phenoxyacetic acid or benzoic acid, were used as new herbicidally active preparations for various plants, and illustrated in Pernak, J., Czerniak, K., Niemczak, M., Chrzanowski, Ł., Ławniczak, Ł., Fochtman, P., Marcinkowska, K., Praczyk, T., New J. Chem., 2015.

The method of obtaining a polymeric material by polymerizing an ionic liquid with a [2- (methacryloyloxy) ethyl] trimethylammonium cation and an inorganic anion is described in patent US8449652 B2. The described polymer is capable of reversible sorption of carbon dioxide. At the same time, it does not absorb other gases and can be used to produce membranes or sorbents.

In turn, the patent US 20150018594 A1 shows the use of ionic liquids with a polymerizable cation and an organic anion to obtain a material resistant to aggressive solvents with high acidity or alkalinity.

The following may be mentioned as specific examples of the ionic liquids of the general formula I:

• 2-methoxyacetate [2- (methacryloyloxy) ethyl] trimethylammonium, • 2- (2-methoxyethoxy) acetate [2- (methacryloyloxy) ethyl] trimethylammonium, • 2- [2- (2-methoxyethoxy) ethoxy] acetate [2- (methacryloyloxy) ethyl] trimethyl ammonium.

The essence of the invention is the new ammonium ionic liquids containing the [2- (methacryloyloxy) ethyl] trimethylammonium cation and an organic anion of the general formula 1, in which A is an anion of the general formula 3: 2-methoxyacetate or 2- (2-methoxyethoxy) acetate , or 2- [2- (2-methoxyethoxy) ethoxy] acetate.

The method of their preparation consists in dissolving the ammonium chloride of formula 2 in an aliphatic alcohol with a carbon chain length from 1 to 4 carbon atoms, preferably in methanol, and mixing in a molar ratio from 1: 0.9 to 1: 1, 3, preferably 1: 1 with an alcoholic sodium salt solution,

Or a potassium, lithium or ammonium acid containing an anion of the general formula 3: 2-methoxyacetate or 2- (2-methoxyethoxy) acetate or 2- [2- (2-methoxyethoxy) ethoxy] acetate at a temperature of 10 to 60 ° C, preferably 20 ° C, for at least 5 minutes, then the solvent is evaporated off and the residue is dried.

The use of new ammonium ionic liquids containing [2- (methacryloyloxy) ethyl] trimethylammonium cation and an organic anion as a cellulose solvent.

Thanks to the solution according to the invention, the following technical and economic effects were obtained:

• synthesized salts are ionic liquids, have a vapor pressure that is not measurable at room temperature, • thanks to the use of cations with an ester group and anions with ether groups, the obtained compounds are biodegradable, • the chemical structure of an anion determines the possibility of interaction with the hydroxyl groups present in the biopolymer structure, which makes that they have the ability to effectively dissolve biopolymers, • the obtained ionic liquids are well soluble in protic solvents and high polarity solvents, • the developed method of synthesis allows for obtaining pure products and ensures high process efficiency, • the possibility of using synthesized ionic liquids as cellulose solvents The invention is illustrated in the following examples:

P r z k ł a d I

Method for the production of [2- (methacryloyloxy) ethyl] trimethylammonium 2-methoxyacetate

[MATMA] [MAc]:

Into a reactor containing a magnetic stirrer was added 55 cm ^{3 of} ethanol, was added 10.4 g (0.05 mol) of [2- (methacryloyloxy) ethyl] trimethylammonium. Then, with continuous stirring, was added 5.8 g (0.045 mol) of potassium methoxyacetate dissolved in 20 cm ³ of ethanol. The pH of the solution was measured using a pH-meter. The reaction was carried out for 1 hour under atmospheric pressure and 10 ° C. Thereafter, the precipitated inorganic salt was filtered off from the system, and then methanol was evaporated using a rotary vacuum evaporator. The compound was then dried at 40 ° C for 12 hours. The reaction yield was 97%.

The structure of the compound was confirmed by performing the proton nuclear magnetic resonance spectrum:

¹ H NMR (DMSO-d ₆ ) δ [ppm] = 1.91 (m, 3H); 3.20 (m, 9H); 3.48 (m, 3H); 3.71 (m, 2H); 3.81 (m, 2H); 4.53 (m, 2H); 5.76 (t, J = 1.6 Hz, 1H); 6.10 (m, 1H).

¹³ C NMR (DMSO-d ₆ ) δ [ppm] = 18.0; 52.9; 57.5; 58.4; 63.8; 72.4; 126.7; 135.4; 166.0; 172.1.

Elemental analysis of CHN for C12H2NO5 (Mmol = 261.31 g / mol): calculated values (%): C = 55.46; H = 8.87; N = 5.36; measured values: C = 54.72; H = 8.51; N = 5.55

P r z x l a d II

Method for the production of [2- (methacryloyloxy) ethyl] trimethylammonium 2- (2-methoxyethoxy) acetate

[MATMA] [MEAc]:

In a reaction vessel provided with a magnetic stirrer 50 cm ³ of methanol and 10.4 g (0.05 mol) of [2- (methacryloyloxy) ethyl] trimethylammonium. Then the stirrer was then introduced into the reactor 7.8 g (0.05 mol) of 2- (2-methoxyethoxy) sodium acetate dissolved in 40 cm ³ of methanol. The reaction was continued for another 40 minutes at 60 ° C and the product solution was separated from the precipitated sodium chloride by filtration under reduced pressure. Thereafter, the solvent was removed from the system and the product was subjected to drying under reduced pressure at 30 ° C for 24 hours to give the final product with a yield of 96%.

The structure of the compound was confirmed by performing the proton nuclear magnetic resonance spectrum:

¹ H NMR (DMSO-d ₆ ) δ [ppm] = 1.91 (m, 3H); 3.21 (m, 9H); 3.41 (m, 3H); 3.51 (m, 2H); 3.56 (m, 4H); 3.77 (m, 2H); 4.55 (m, 2H); 5.76 (t, J = 1.6 Hz, 1H); 6.10 (m, 1H).

GB 230 028 B1 ¹³ C NMR (DMSO-cfe) δ [ppm] = 18.0; 52.9, 58.0; 58.5; 63.8; 68.7; 71.2; 71.5; 126.7; 135.5; 166.1;

172.4.

Elemental analysis of CHN for C14H27NO6 (Mmol = 305.37 g / mol): calculated values (%): C = 55.06; H = 8.91; N = 4.59; measured values: C = 55.36; H = 9.18; N = 4.65.

P r x l a d III

Preparation of 2- [2- (2-methoxyethoxy) ethoxy] [2- (methacryloyloxy) ethyl] trimethylammonium acetate [MATMA] [MEEAc]:

In a reactor equipped with a magnetic stirrer and charged with 20.7 g (0.1 mol) of [2- (methacryloyloxy) ethyl] trimethylammonium dissolved in 100 cm ^{3 of} propan-2-ol. Then stirring was started and fed to the reactor 20.3 g (0.11 mol) of the lithium salt of 2- [2- (2-methoxyethoxy) ethoxy] acetic acid dissolved in 95 cm ^{3 of} isopropanol. The solution was stirred for 1 hour at 20 ° C. After the reaction system was cooled to 5 ° C, the mixture was filtered under reduced pressure to remove the precipitated inorganic salt from the system. Thereafter, the isopropanol was stripped from the system, and the main reaction product was dried in vacuo for 12 hours at 40 ° C. The reaction yield was 94%.

The structure of the compound was confirmed by performing the proton nuclear magnetic resonance spectrum:

¹ H NMR (DMSO-d ₆ ) δ [ppm] = 1.91 (dd, J = 1.6; 1.0 Hz, 3H); 3.22 (s, 9H); 3.43 (m, 3H); 3.50 (m, 2H); 3.69 (m, 8H); 3.84 (m, 2H); 4.54 (m, 2H); 5.76 (t, J = 1.6 Hz, 1H), 6.10 (m, 1H).

¹³ C NMR (DMSO-d ₆ ) δ [ppm] = 17.9; 52.8; 58.0; 58.4; 63.7; 68.8; 69.4; 69.9; 71.3; 71.4; 126.6; 135.4; 165.9; 171.9.

Elemental analysis of CHN for C16H31NO7 (Mmol = 349.42 g / mol): calculated values (%): C = 55.00; H = 8.94; N = 4.01; measured values: C = 54.64; H = 9.32; N = 3.81

P r x l a d IV

Method for the production of [2- (methacryloyloxy) ethyl] trimethylammonium 2-methoxyacetate

[MATMA] [MAc]:

For equipped with magnetic stirrer reactor was charged with 120 cm ^{3 of} butan-1-ol, was added 31.1 g (0.15 mol) of [2- (methacryloyloxy) ethyl] trimethylammonium. Then stirring was started and added 16.1 g (0.15 mol) of 2-methoxyacetate, ammonium, dissolved in 100 cm ^{3 of} butanol. The reaction was carried out for another 80 minutes at 20 ° C. The stirring was then turned off and the precipitated ammonium chloride was filtered off from the reaction system. The solvent was then evaporated on a vacuum evaporator. The resulting compound was placed in a vacuum oven at 30 ° C for 24 hours. The reaction yield was 96%.

The structure of the compound was confirmed by performing the proton nuclear magnetic resonance spectrum:

¹ H NMR (DMSO-d ₆ ) δ [ppm] = 1.91 (m, 3H); 3.19 (m, 9H); 3.45 (m, 3H); 3.72 (m, 2H); 3.81 (m, 2H); 4.54 (m, 2H); 5.76 (t, J = 1.6 Hz, 1H); 6.10 (m, 1H).

¹³ C NMR (DMSO-d ₆ ) δ [ppm] = 18.0; 52.9; 57.7; 58.4; 63.7; 71.9; 126.6; 135.4; 166.0; 172.3.

Elemental analysis of CHN for C12H2NO5 (Mmol = 261.31 g / mol): calculated values (%): C = 55.46; H = 8.87; N = 5.36; measured values: C = 54.91; H = 8.62; N = 5.12

Application example

An example of the use of ionic liquids as a cellulose solvent for the production of processed cellulose

0.135 g of microcrystalline cellulose and 2.865 g of [2- (methacryloyloxy) ethyl] trimethyl ammonium 2-methoxyacetate were placed in a reaction vessel containing a magnetic stirrer. Thereafter, 4-methoxyphenol was added to the mixture in an amount corresponding to a concentration of 2000 ppm to prevent reaction at a concentration of 2000 ppm to prevent polymerization reaction. The system was stirred for 5 hours at the temperature of 50 ° C.

After 5 hours, the system temperature was increased rapidly to 100 ° C. The system was agitated for 60 seconds until the cellulose was completely dissolved. The percentage by weight of dissolved cellulose in the solution was 4.5%. Table 1 shows the maximum solubility of cellulose in the obtained ionic liquids. Table 1 shows the maximum solubility of cellulose in ionic liquids with the MATMA cation.

PL 230 028 B1

T a b e l a 1

Relationship name Maximal cellulose solubility (%) [MATMA] [MAc] 4.5 [MATMA] [MEAc] 4.0 [MATMA] [MEEAc] 3.5

Methanol was then added to a saturated cellulose-ionic liquid system to precipitate the dissolved cellulose. The obtained processed biopolymer is used to obtain monosaccharides by enzymatic hydrolysis.

Claims (3)

1. New ammonium ionic liquids containing [2- (methacryloyloxy) ethyl] trimethylammonium cation and an organic anion of the general formula 1, in which A is an anion of the general formula 3: 2-methoxyacetate or 2- (2-methoxyethoxy) acetate, or 2- [2- (2-methoxy-ethoxy) ethoxy] acetate. 2. A method for obtaining new ammonium ionic liquids according to claim 1, A process as claimed in claim 1, characterized in that the ammonium chloride of formula 2 is dissolved in an aliphatic alcohol with a carbon chain length of 1 to 4 carbon atoms, preferably methanol, and mixed in a molar ratio of 1: 0.9 to 1: 1.3, preferably 1: 1 with an alcoholic solution of a sodium or potassium or lithium or ammonium salt of an acid containing an anion of the general formula 3: 2-methoxyacetate or 2- (2-methoxyethoxy) acetate or 2- [2- (2-methoxyethoxy) ethoxy ] acetate at a temperature of 10 to 60 ° C, preferably 20 ° C, for at least 5 minutes, then the solvent is evaporated off and the residue is dried. 3. Application of new ammonium ionic liquids containing [2- (methacryloyloxy) ethyl] trimethylammonium cation and organic anion as cellulose solvent.