Carboxylic acid ester production method

Abstract

Provided is a production method whereby corresponding carboxylic acid esters can be obtained from a variety of carboxylic acids at a high yield, even under conditions using a simple reaction operation and little catalyst and even if the amount of substrate used is theoretical. A production method for carboxylic acid ester, whereby a prescribed diester dicarbonate, carboxylic acid, and alcohol are reacted in the presence of at least one type of magnesium compound and at least one type of alkali metal compound.

Claims

1. A method, comprising: reacting a compound represented by formula (I): ##STR00003## where R.sup.1 and R.sup.2 each independently are a C1-C20 hydrocarbon group with a carboxylic acid and an alcohol in the presence of at least one magnesium compound and at least one alkali metal compound to produce a carboxylic acid ester from said carboxylic acid and said alcohol.

2. The method according to claim 1, wherein the alkali metal compound comprises lithium.

3. The method according to claim 1, wherein the compound represented by the formula (I) is di-t-butyl dicarbonate.

4. The method according to claim 1, wherein the carboxylic acid is a (meth)acrylic acid.

5. The method according to claim 1, wherein the alcohol is an aromatic alcohol.

6. The method according to claim 1, wherein said reacting is carried out by adding 0.1-10 mol of the carboxylic acid and 0.1-10 mol of the alcohol relative to 1 mol of the compound represented by the formula (I).

7. The method according to claim 1, wherein said reacting is carried out in the presence of the magnesium compound and alkali metal compound, each being set at 0.001-1000 mol % of the alcohol.

8. The method according to claim 1, wherein said carboxylic acid is a compound represented by the formula R.sup.3COOH where R.sup.3 is a C1-C30 hydrocarbon group that may have a substituent, said alcohol is a compound represented by the formula R.sup.4OH where R.sup.4 is a C1-C30 hydrocarbon group that may have a substituent, and said carboxylic acid ester is a compound represented by the formula R.sup.3COOR.sup.4 where R.sup.3 and R.sup.4 are as described for the formulae R.sup.3COOH and R.sup.4OH.

9. The method according to claim 1, wherein the compound represented by the formula (I) is di-t-butyl dicarbonate, the carboxylic acid is (meth)acrylic acid, the alcohol is phenol, and the carboxylic acid ester is phenyl (meth)acrylate.

10. The method according to claim 1, wherein the at least one magnesium compound is selected from magnesium oxide, magnesium hydroxide, magnesium carbonate hydroxide, magnesium sulfate, ammonium magnesium sulfate, magnesium nitrate, magnesium chloride, magnesium bromide, magnesium acetate, magnesium benzoate, magnesium (meth)acrylate, and magnesium acetylacetonate, and the at least one alkali metal compound is selected from lithium oxide, lithium hydroxide, lithium carbonate, lithium fluoride, lithium chloride, lithium bromide, lithium acetate, lithium benzoate, lithium (meth)acrylate, lithium amide, lithium triflimide, and lithium acetylacetonate.

11. The method according to claim 10, wherein said carboxylic acid is a compound represented by the formula R.sup.3COOH where R.sup.3 is a C1-C30 hydrocarbon group that may have a substituent, said alcohol is a compound represented by the formula R.sup.4OH where R.sup.4 is a C1-C30 hydrocarbon group that may have a substituent, and said carboxylic acid ester is a compound represented by the formula R.sup.3COOR.sup.4 where R.sup.3 and R.sup.4 are as described for the formulae R.sup.3COOH and R.sup.4OH.

12. The method according to claim 10, wherein the compound represented by the formula (I) is di-t-butyl dicarbonate, the carboxylic acid is (meth)acrylic acid, the alcohol is phenol, and the carboxylic acid ester is phenyl (meth)acrylate.

13. The method according to claim 1, wherein the compound represented by the formula (I) is di-t-butyl dicarbonate, the carboxylic acid is a (meth)acrylic acid, the alcohol is phenol, and the carboxylic acid ester is phenyl (meth)acrylate, and wherein the at least one magnesium compound is selected from magnesium acetylacetonate, and the at least one alkali metal compound is selected from lithium hydroxide monohydrate, cesium hydroxide monohydrate, lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, lithium oxide, lithium acetylacetonate, lithium fluoride, lithium chloride, lithium bromide, lithium amide, and lithium triflimide.

Description

EXAMPLES

(1) In the following, the present invention is described in detail by referring to examples. However, the present invention is not limited to those examples, and any modification is possible unless it deviates from the gist of the present invention.

(2) The di-t-butyl dicarbonate used in the examples and comparative examples below is a compound with a purity of 98 mass % made by Tokyo Chemical Industry Co., Ltd., and R.sup.1 and R.sup.2 in formula (I) are C(CH.sub.3).sub.3. In addition, tetrahydrofuran (hereinafter abbreviated as THF) is a special grade (moisture rate of 0.05% or less) made by Kanto Chemical Co., Inc. The method for determining the yield of each product is as follows.

(3) After the reaction was completed, a standard substance (anisole or 1,1,2,2-tetrachloroethane) was added to the reaction mixture. Then, the mixture was dissolved in deuterated chloroform (CDCl.sub.3) and was analyzed by .sup.1H-NMR (270 MHz). By converting from the values obtained from integration of the signal intensities on the spectrum, the amount (mmol) of the produced carboxylic acid ester was determined. Next, the yield of the carboxylic acid ester was calculated by formula (1) (when the obtained yield is less than 1%, it will be denoted as zero).
Yield of carboxylic acid ester (%)=(P.sub.1/R.sub.1)100(1)

(4) P.sub.1=the amount of produced carboxylic acid ester (mmol)

(5) R.sub.1=the amount of alcohol used in the reaction (mmol)

(6) Also, the amount (mol %) of each magnesium compound and alkali metal compound used as the catalyst was calculated by formula (2).
The amount of catalyst (mol %)=(C.sub.1/R.sub.1)100(2)

(7) C.sub.1=the amount of catalyst used in the reaction (mmol)

(8) R.sub.1=the amount of alcohol used in the reaction (mmol)

Example 1

(9) In a 100 mL capacity eggplant-shaped flask, 10.000 grams (106.26 mmol) of phenol, 9.148 grams (106.26 mmol) of methacrylic acid, 23.664 grams (106.26 mmol) of di-t-butyl dicarbonate, 0.018 grams (0.43 mmol, 0.4 mol %) of lithium hydroxide monohydrate, and 0.024 grams (0.11 mmol, 0.1 mol %) of magnesium acetylacetonate were added successively. Then reaction was carried out at 25 C. while the mixture was stirred. Accordingly, phenyl methacrylate was produced. The reaction result obtained 5 hours after the start of reaction is shown in Table 1.

Examples 214

(10) In each of the examples, phenyl methacrylate was produced by conducting the same procedure as in Example 1 except that lithium hydroxide monohydrate as the catalyst was replaced with a type of alkali metal compound (0.4 mol %) shown in Table 1. The reaction result obtained 5 hours after the start of reaction in each example is shown in Table 1.

Comparative Example 1

(11) Phenyl methacrylate was produced by carrying out the same procedure as in Example 1 except that lithium hydroxide monohydrate was not added. The reaction result obtained 5 hours after the start of reaction is shown in Table 1.

Comparative Example 2

(12) The comparative example was conducted in an attempt to produce phenyl methacrylate by carrying out the same procedure as in Example 1 except that magnesium acetylacetonate was not added. The reaction result obtained 5 hours after the start of reaction is shown in Table 1.

Comparative Example 3

(13) The comparative example was conducted in an attempt to produce phenyl methacrylate by carrying out the same procedure as in Comparative Example 2 except that the amount of lithium hydroxide monohydrate was changed to 2.0 mol %. The reaction result obtained 24 hours after the start of reaction is shown in Table 1.

Comparative Examples 410

(14) Each comparative example was conducted in an attempt to produce phenyl methacrylate by the same procedure as in Comparative Example 2 except that lithium hydroxide monohydrate was replaced with a type and amount of alkali metal compound (1.0 mol % or 2.0 mol %) specified in Table 1. The reaction result of each comparative example obtained 24 hours after the start of reaction is shown in Table 1.

(15) TABLE-US-00001 TABLE 1 yield of added added reaction phenyl magnesium amount alkali metal amount time methacrylate compound (mol %) compound (mol %) (hr.) (%) Example 1 magnesium 0.1 lithium hydroxide 0.4 5 82 acetylacetonate monohydrate Example 2 magnesium 0.1 cesium hydroxide 0.4 5 56 acetylacetonate monohydrate Example 3 magnesium 0.1 lithium carbonate 0.4 5 78 acetylacetonate Example 4 magnesium 0.1 sodium carbonate 0.4 5 72 acetylacetonate Example 5 magnesium 0.1 potassium carbonate 0.4 5 68 acetylacetonate Example 6 magnesium 0.1 rubidium carbonate 0.4 5 53 acetylacetonate Example 7 magnesium 0.1 cesium carbonate 0.4 5 42 acetylacetonate Example 8 magnesium 0.1 lithium oxide 0.4 5 73 acetylacetonate Example 9 magnesium 0.1 lithium acetylacetonate 0.4 5 67 acetylacetonate Example 10 magnesium 0.1 lithium fluoride 0.4 5 77 acetylacetonate Example 11 magnesium 0.1 lithium chloride 0.4 5 82 acetylacetonate Example 12 magnesium 0.1 lithium bromide 0.4 5 86 acetylacetonate Example 13 magnesium 0.1 lithium amide 0.4 5 82 acetylacetonate Example 14 magnesium 0.1 lithium triflimide 0.4 5 71 acetylacetonate Comp. magnesium 0.1 5 19 Example 1 acetylacetonate Comp. lithium hydroxide Example 2 monohydrate 0.4 5 0 Comp. lithium hydroxide Example 3 monohydrate 2.0 24 0 Comp. cesium hydroxide Example 4 monohydrate 2.0 24 0 Comp. lithium carbonate 2.0 24 0 Example 5 Comp. sodium carbonate 2.0 24 0 Example 6 Comp. potassium carbonate 2.0 24 0 Example 7 Comp. rubidium carbonate 2.0 24 0 Example 8 Comp. cesium carbonate 2.0 24 0 Example 9 Comp. lithium bromide 1.0 24 0 Example 10

Examples 1519

(16) In each example, phenyl methacrylate was produced by carrying out the same procedure as in Example 1 except that the amount of lithium hydroxide monohydrate (0.1 mol %2.0 mol %) specified in Table 2 was used. The reaction result of each example obtained 5 hours or 24 hours after the start of reaction is shown in Table 2.

(17) TABLE-US-00002 TABLE 2 yield of added added reaction phenyl magnesium amount alkali metal amount time methacrylate compound (mol %) compound (mol %) (hr.) (%) Example 15 magnesium 0.1 lithium hydroxide 0.1 5 90 acetylacetonate monohydrate 24 94 Example 16 magnesium 0.1 lithium hydroxide 0.2 5 86 acetylacetonate monohydrate 24 95 Example 17 magnesium 0.1 lithium hydroxide 0.4 5 82 acetylacetonate monohydrate 24 96 Example 18 magnesium 0.1 lithium hydroxide 0.8 24 96 acetylacetonate monohydrate Example 19 magnesium 0.1 lithium hydroxide 2.0 24 96 acetylacetonate monohydrate

Examples 2031

(18) In each example, phenyl methacrylate was produced by carrying out the same procedure as in Example 1 except that magnesium acetylacetonate was replaced with the type and amount of magnesium compound (0.05 mol %0.5 mol %) specified in Table 3, and the amount of lithium hydroxide monohydrate specified in Table 3 was used (0.2 mol %2.0 mol %). The reaction result of each example obtained 5 hours or 24 hours after the start of reaction is shown in Table 3.

Comparative Examples 1122

(19) Each comparative example was conducted to produce, or in an attempt to produce, phenyl methacrylate by carrying out the same procedure as in Examples 2031 except that lithium hydroxide monohydrate was not added. The reaction result of each comparative example obtained 5 hours or 24 hours after the start of reaction is shown in Table 3.

(20) TABLE-US-00003 TABLE 3 yield of added added reaction phenyl magnesium amount alkali metal amount time methacrylate compound (mol %) compound (mol %) (hr.) (%) Example 20 magnesium acetate 0.05 lithium hydroxide 0.2 24 93 tetrahydrate monohydrate Example 21 magnesium benzoate 0.05 lithium hydroxide 0.2 24 93 trihydrate monohydrate Example 22 magnesium 0.05 lithium hydroxide 0.2 24 93 methacrylate monohydrate Example 23 magnesium hydroxide 0.1 lithium hydroxide 0.4 5 81 monohydrate Example 24 magnesium chloride 0.1 lithium hydroxide 0.4 5 84 monohydrate Example 25 magnesium chloride 0.2 lithium hydroxide 0.8 5 67 hexahydrate monohydrate Example 26 magnesium bromide 0.2 lithium hydroxide 0.8 5 85 hexahydrate monohydrate Example 27 magnesium nitrate 0.2 lithium hydroxide 0.8 5 82 hexahydrate monohydrate Example 28 magnesium sulfate 0.2 lithium hydroxide 0.8 24 92 monohydrate Example 29 ammonium magnesium 0.2 lithium hydroxide 0.8 24 46 sulfate hexahydrate monohydrate Example 30 magnesium oxide 0.5 lithium hydroxide 2.0 24 97 monohydrate Example 31 magnesium carbonate 0.5 lithium hydroxide 2.0 24 96 hydroxide monohydrate Comp. magnesium acetate 0.05 24 88 Example 11 tetrahydrate Comp. magnesium benzoate 0.05 24 85 Example 12 trihydrate Comp. magnesium 0.05 24 88 Example 13 methacrylate Comp. magnesium hydroxide 0.1 5 49 Example 14 Comp. magnesium chloride 0.1 5 0 Example 15 Comp. magnesium chloride 0.2 5 1 Example 16 hexahydrate Comp. magnesium bromide 0.2 5 1 Example 17 hexahydrate Comp. magnesium nitrate 0.2 5 5 Example 18 hexahydrate Comp. magnesium sulfate 0.2 24 0 Example 19 Comp. ammonium magnesium 0.2 24 0 Example 20 sulfate hexahydrate Comp. magnesium oxide 0.5 24 74 Example 21 Comp. magnesium carbonate 0.5 24 64 Example 22 hydroxide

Example 32

(21) In a 100 mL capacity eggplant-shaped flask, 10.000 grams (106.26 mmol) of phenol, 7.657 grams (106.26 mmol) of acrylic acid, 23.664 grams (106.26 mmol) of di-t-butyl dicarbonate, 0.046 grams (0.53 mmol, 0.5 mol %) of lithium bromide, and 0.064 grams (0.53 mmol, 0.5 mol %) of magnesium sulfate were added successively. Then, reaction was carried out at 25 C. while the mixture was stirred. Accordingly, phenyl acrylate was produced. The reaction result obtained 24 hours after the start of reaction is shown in Table 4.

Examples 3335

(22) Phenyl acrylate was produced in each of the examples by conducting the same procedure as in Example 32 except that lithium bromide was replaced with a type of alkali metal compound (0.5 mol %) specified in Table 4. The reaction result of each example obtained 24 hours after the start of reaction is shown in Table 4.

Comparative Example 23

(23) The comparative example was conducted in an attempt to produce phenyl acrylate by the same procedure as in Example 32 except that lithium bromide was not added. The reaction result obtained 24 hours after the start of reaction is shown in Table 4.

Comparative Example 24

(24) The comparative example was conducted in an attempt to produce phenyl acrylate by the same procedure as in Example 32 except that magnesium sulfate was not added. The reaction result obtained 24 hours after the start of reaction is shown in Table 4.

(25) TABLE-US-00004 TABLE 4 yield of added added reaction phenyl magnesium amount alkali metal amount time acrylate compound (mol %) compound (mol %) (hr.) (%) Example 32 magnesium 0.5 lithium bromide 0.5 24 48 sulfate Example 33 magnesium 0.5 lithium 0.5 24 68 sulfate acetylacetonate Example 34 magnesium 0.5 lithium carbonate 0.5 24 77 sulfate Example 35 magnesium 0.5 lithium hydroxide 0.5 24 78 sulfate monohydrate Comp. magnesium 0.5 24 0 Example 23 sulfate Comp. lithium bromide 0.5 24 0 Example 24

Example 36

(26) In a 1 L capacity eggplant-shaped flask, 153.370 grams (1629.69 mmol) of phenol, 140.300 grams (1629.69 mmol) of methacrylic acid, 362.938 grams (1629.69 mmol) of di-t-butyl dicarbonate, 0.027 grams (0.65 mmol, 0.04 mol %) of lithium hydroxide monohydrate, and 0.010 grams (0.16 mmol, 0.01 mol %) of magnesium hydroxide were added successively. Then reaction was carried out at 25 C. while the mixture was stirred. Accordingly, phenyl methacrylate was produced. The reaction result obtained 48 hours after the start of reaction is shown in Table 5.

Examples 3762

(27) By using the material, catalyst and solvent shown in Tables 57 under the conditions specified in those tables and a smaller eggplant-shaped flask when applicable, corresponding carboxylic acid esters were produced by conducting the same procedure as in Example 36. The reaction results are shown in Tables 57.

(28) TABLE-US-00005 TABLE 5 added compound by added carboxylic acid amount formula (I) alcohol magnesium amount alkali metal (mol eq.) (mmol) (mol eq.) (mol eq.) compound (mol %) compound Example 36 methacrylic acid 1629.69 di-t-butyl phenol magnesium 0.01 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 37 methacrylic acid 815.43 di-t-butyl 2-phenylphenol magnesium 0.02 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 38 methacrylic acid 326.40 di-t-butyl 4-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 39 methacrylic acid 815.43 di-t-butyl 1-naphthol magnesium 0.02 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 40 methacrylic acid 326.40 di-t-butyl 2-naphthol magnesium 0.05 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 41 methacrylic acid 326.40 di-t-butyl 2-naphthol magnesium 0.05 lithium (1.00) dicarbonate (1.00) hydroxide hydroxide (1.00) monohydrate Example 42 methacrylic acid 1800.02 di-t-butyl phenol magnesium 0.01 lithium (1.00) dicarbonate (0.91) hydroxide hydroxide (1.00) monohydrate Example 43 methacrylic acid 1800.02 di-t-butyl phenol magnesium 0.01 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) yield of added reaction reaction carboxylic amount solvent temp. time acid ester (mol %) (mL) ( C.) (hr.) (%) Example 36 0.04 25 48 96 Example 37 0.2 25 24 98 Example 38 0.5 THF 25 24 96 (215) Example 39 0.2 25 24 98 Example 40 0.5 THF 25 24 91 (110) Example 41 0.5 THF 40 5 97 (110) Example 42 0.04 25 48 97 Example 43 0.05 25 48 91

(29) TABLE-US-00006 TABLE 6 added compound by added carboxylic acid amount formula (I) alcohol magnesium amount alkali metal (mol eq.) (mmol) (mol eq.) (mol eq.) compound (mol %) compound Example 44 acrylic acid 358.67 di-t-butyl 2-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 45 acrylic acid 358.67 di-t-butyl 2-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 46 acrylic acid 358.67 di-t-butyl 2-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 47 acrylic acid 358.67 di-t-butyl 2-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 48 acrylic acid 358.67 di-t-butyl 4-phenylphenol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 49 acrylic acid 358.60 di-t-butyl 1-naphthol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide hydroxide (1.00) monohydrate Example 50 acrylic acid 358.60 di-t-butyl 1-naphthol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 51 acrylic acid 358.60 di-t-butyl 1-naphthol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) Example 52 acrylic acid 358.60 di-t-butyl 2-naphthol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide hydroxide (1.00) monohydrate Example 53 acrylic acid 358.60 di-t-butyl 2-naphthol magnesium 0.05 lithium (1.00) dicarbonate (0.91) hydroxide carbonate (1.00) yield of added reaction reaction carboxylic amount solvent temp. time acid ester (mol %) (mL) ( C.) (hr.) (%) Example 44 0.25 25 24 82 Example 45 0.25 50 6 92 Example 46 0.25 THF 25 24 98 (30) Example 47 0.25 THF 50 6 98 (30) Example 48 0.25 THF 25 24 97 (30) Example 49 0.25 25 24 94 Example 50 0.25 25 24 94 Example 51 0.25 50 6 95 Example 52 0.25 25 24 92 Example 53 0.25 25 24 95

(30) TABLE-US-00007 TABLE 7 added compound by added carboxylic acid amount formula (I) alcohol magnesium amount alkali metal (mol eq.) (mmol) (mol eq.) (mol eq.) compound (mol %) compound Example 54 heptanoic acid 342.52 di-t-butyl phenol magnesium 0.05 lithium (1.00) dicarbonate (0.95) hydroxide hydroxide (1.00) monohydrate Example 55 cyclohexane 342.52 di-t-butyl phenol magnesium 0.05 lithium carboxylic acid dicarbonate (0.95) hydroxide hydroxide (1.00) (1.00) monohydrate Example 56 cyclohexane 342.52 di-t-butyl phenol magnesium 0.05 lithium carboxylic acid dicarbonate (0.95) hydroxide carbonate (1.00) (1.00) Example 57 pivalic acid 342.52 di-t-butyl phenol magnesium 0.05 lithium (1.00) dicarbonate (0.95) hydroxide hydroxide (1.00) monohydrate Example 58 benzoic acid 342.52 di-t-butyl phenol magnesium 0.05 lithium (1.00) dicarbonate (0.95) hydroxide hydroxide (1.00) monohydrate Example 59 benzoic acid 342.52 di-t-butyl phenol magnesium 0.05 lithium (1.00) dicarbonate (0.95) hydroxide hydroxide (1.00) monohydrate Example 60 adipic acid 163.64 di-t-butyl phenol magnesium 0.1 lithium monomethyl dicarbonate (1.00) hydroxide hydroxide (1.00) (1.00) monohydrate Example 61 adipic acid 163.64 di-t-butyl phenol magnesium 1.0 lithium monomethyl dicarbonate (1.00) hydroxide hydroxide (1.00) (1.00) monohydrate Example 62 6-chlorohexanoic 23.38 di-t-butyl phenol magnesium 1.0 lithium acid dicarbonate (1.00) hydroxide hydroxide (1.00) (1.00) monohydrate yield of added reaction reaction carboxylic amount solvent temp. time acid ester (mol %) (mL) ( C.) (hr.) (%) Example 54 0.25 25 24 95 Example 55 0.25 25 24 98 Example 57 0.25 25 24 98 Example 57 0.25 25 24 77 Example 58 0.25 THF 25 24 88 (80) Example 59 0.25 THF 50 4 94 (80) Example 60 0.5 25 24 96 Example 61 1.0 25 6 90 Example 62 1.0 25 6 94

INDUSTRIAL APPLICABILITY

(31) The method for producing a carboxylic acid ester related to the present invention is capable of producing the carboxylic acid ester more efficiently and cost-effectively than in conventional methods. In addition, by using the method for producing a carboxylic acid ester related to the present invention, a carboxylic acid ester is obtained at high yield under mild reaction conditions. Furthermore, since various carboxylic acids and alcohols may be used as raw materials in the method for producing a carboxylic acid ester related to the present invention, the substrate generality is significantly broader than in conventional methods.

(32) The present application is based upon and claims the benefit of Japanese Patent Application No. 2014-255665, filed on Dec. 18, 2014. The entire contents of the application are incorporated herein by reference.

(33) So far, the present invention has been described with reference to the embodiments and examples. However, the present invention is not limited to those embodiments and examples. Unless deviating from the gist of the present invention, various modifications to the structure and details of the present invention may be made within the scope that will be apparent to those skilled in the art.