Abstract:
The present invention relates to monomers for preparing photoresist polymer resins which can be used in a photolithography process employing a deep ultraviolet light source, and the preparation of the same. Preferred monomers are represented by following Chemical Formula 1: 
     &lt;Chemical Formula 1&gt;                            
     wherein, X represents CH 2 , CH 2 CH 2 , or oxygen; 
     R 1  represents hydrogen, C 1 -C 5  alkyl, or R′OH; 
     R 2  represents hydrogen; —OH, C 1 -C 5  alkoxy, or —OR′—OH; 
     R′ represents:                            
      and, 
     m is an integer from 1-5, n is 1 or 2 and p is 0 or 1.

Description:
FIELD OF THE INVENTION 
     The present invention relates to novel monomers used for preparing a photoresist copolymer, and a process for preparing the same. More specifically, it relates to monomers useful for forming photoresist polymer resins which have suitable properties for lithography processes using a light source employing deep ultraviolet region radiation, and a process for preparing the same. 
     BACKGROUND OF THE INVENTION 
     In general, excellent etching resistance, heat resistance, adhesiveness and resolution are requisites for a photoresist resin. However, most of the conventional ArF photoresists have insufficient etching resistance, and cannot fully satisfy those properties. For example, the photoresist polymer resins comprising an alicyclic compound as a monomer have excellent etching resistance and resolution, but the absorbance of the photoresist at the wavelength of ArF light is so high that a pattern of high integrity and high resolution could not be obtained. 
     SUMMARY OF THE INVENTION 
     The object of the present invention is to solve the problems described above, and to provide novel photoresist monomers which impart excellent etching resistance and adhesiveness to photoresist polymers so as to be suitable for lithography processes using a deep ultraviolet light source. 
     Through intensive studies and research, the present inventors have developed monomers that can overcome the problems associated with developing a high-performance photoresist. As a result, they have found that when a compound having one or more hydroxyl groups or alkoxy groups, such as a compound of Chemical Formula 1 below, is used as a monomer for preparing a photoresist copolymer, adhesiveness of the photoresist to a silicon wafer is considerably enhanced, and a resist having excellent resolution and etching resistance can be developed. 
     The present invention provides a novel photoresist monomer represented by following Chemical Formula 1: 
     &lt;Chemical Formula 1&gt;                           
     wherein, X represents CH 2 , CH 2 CH 2 , or oxygen; 
     R 1  represents hydrogen, C 1 -C 5  alkyl, or R′OH; 
     R 2  represents hydrogen; —OH, C 1 -C 5  alkoxy, or —OR′—OH; 
     R′ represents:                           
      and 
     m is an integer from 1-5, n is 1 or 2 and p is 0 or 1. 
     Preferably R′OH is selected from the group consisting of the following groups (2)-(9):                           
     The compounds of Chemical Formula 1 are synthesized by reacting (i) a compound represented by Chemical Formula 2 below with (ii) an alkyl compound having one or more hydroxyl group(s), in the presence of a base or acid catalyst in an organic solvent.                           
     wherein, X represents CH 2 , CH 2 CH 2 , or oxygen. 
     Examples of suitable alkyl compounds having hydroxyl substituent(s) include methanol, ethanol, propanol, ethylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-pentanediol, diethylene glycol, triethylene glycol, 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,3-cyclopentanedimethanol, 1,2-cyclopentanedimethanol, 1,3-cyclopentanediol, and 1,2-cyclopentanediol. 
     As the acid catalyst, sulfuric acid, hydrochloric acid, nitric acid or acetic acid may be used. As the base catalyst, sodium hydride (NaH), potassium hydride (KH), calcium hydride (CaH 2 ) or lithium diisopropyl amide (LDA) may be used. As the reaction solvent, tetrahydrofuran (THF), dimethylformamide, dimethylsulfoxide, dioxane, benzene, toluene, or xylene may be used. 
     The compounds according to the present invention can be effectively used as a monomer for synthesizing a photoresist resin for electron-beam, ArF, KrF, EUV, VUV (Vacuum Ultra Violet) and X-ray radiation, which can be employed in micro lithography processes to form high-integrity patterns of 0.15 μm or less (DRAM of 1G or more). Since the monomers according to the present invention comprise one or more hydroxyl group or alkoxy group, adhesiveness can be considerably enhanced when they are employed in the synthesis of a photoresist resin, and a resist having excellent resolution and etching resistance can be developed therefrom. 
     Photoresist copolymer resins may be prepared by polymerizing a monomer of Chemical Formula 1 with at least one other monomer, for example with one or more alicyclic olefin monomers. Polymerization may be carried out using conventional bulk polymerization or solution polymerization processes. 
    
    
     DETAILED DESCRIPTION 
     The invention is described in more detail by referring to the examples below, but it should be noted that the present invention is not restricted to the examples. 
     EXAMPLE 1 
     Synthesis of 5-norbornene-2-(1-methoxy)methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and methanol (500 ml) were reacted at room temperature for 10 hours. After the reaction was completed, methanol was distilled off by using a rotary evaporator. To the residual solution, 200 ml of water and 300 ml of ethyl acetate were added, and the mixture was extracted. The organic layer was washed with water (300 ml) once more, dried over anhydrous magnesium sulfate and filtered. The filtrate was evaporated by using a rotary evaporator. The residue was distilled under high vacuum to obtain the compound of Chemical Formula 3 as a colorless and clear liquid (13 g/yield: 93%).                           
     EXAMPLE 2 
     Synthesis of 5-norbornene-2-(1-ethoxy)methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and ethanol (500 ml) were reacted at room temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 4 as a colorless and clear liquid (15 g/yield: 91%).                           
     EXAMPLE 3 
     Synthesis of 5-norbornene-2-(1-propyloxy)methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and propanol (500 ml) were reacted at room temperature for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 5 as a colorless and clear liquid (17 g/yield: 91%).                           
     EXAMPLE 4 
     Synthesis of 5-norbornene-2-hydroxyethoxymethanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and ethylene glycol (100 ml) were reacted at room temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 6 as a colorless and clear liquid (16 g/yield: 89%).                           
     EXAMPLE 5 
     Synthesis of 5-norbornene-2-hydroxypropyloxy methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and trimethylene glycol (100 ml) were reacted at room temperature for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 7 as a colorless and clear liquid (17 g/yield: 85%).                           
     EXAMPLE 6 
     Synthesis of 5-norbornene-2-hydroxybutyloxy methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and 1,4-butanediol (100 ml) were reacted at room temperature for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 8 as a colorless and clear liquid (18 g/yield: 86%).                           
     EXAMPLE 7 
     Synthesis of 5-norbornene-2-hydropentyloxy methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and 1,5-pentanediol (100 ml) were reacted at room temperature for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 9 as a colorless and clear liquid (19 g/yield: 83%).                           
     EXAMPLE 8 
     Synthesis of 5-norbornene-2-hydroxyethoxyethoxy methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and diethylene glycol (100 ml) were reacted at 80° C. for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 1, to obtain the compound of Chemical Formula 10 as a colorless and clear liquid (20 g/yield: 85%).                           
     EXAMPLE 9 
     Synthesis of 5-norbornene-2-hydroxyethoxy methanol 
     5-norbornene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and triethylene glycol (100 ml) were reacted at room temperature for 12 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 2, to obtain the compound of Chemical Formula 11 as a colorless and clear liquid (22 g/yield: 79%).                           
     EXAMPLE 10 
     Synthesis of 5-norbornene-2-(4-hydroxymethyl) cyclohexylmethoxymethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,4-cyclohexanedimethanol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (300 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated by a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 12 as a colorless and clear liquid (25 g/yield: 93%).                           
     EXAMPLE 11 
     Synthesis of 5-norbornene-2-(3-hydroxymethyl) cyclohexylmethoxymethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclohexanedimethanol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (300 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated by a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 13 as a colorless and clear liquid (24 g/yield: 91%).                           
     EXAMPLE 12 
     Synthesis of 5-norbornene-2-(3-hydroxy) cyclohexyloxy methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclohexanediol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (300 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated by a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 14 as a colorless and clear liquid (21 g/yield: 88)%.                           
     EXAMPLE 13 
     Synthesis of 5-norbornene-2-(4-hydroxy)cyclohexyloxy methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,4-cyclohexanediol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (300 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated by a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 15 as a colorless and clear liquid (22 g/yield: 92%).                           
     EXAMPLE 14 
     Synthesis of 5-norbornene-2-(3-hydroxymethyl)cyclopentylnethoxy methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclopentanedimethanol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 11, to obtain the compound of Chemical Formula 16 as a colorless and clear liquid (23 g/yield: 90%).                           
     EXAMPLE 15 
     Synthesis of 5-norbornene-2-(2-hydroxymethyl) cyclopentylmethoxymethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,2-cyclopentanedimethanol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 11, to obtain the compound of Chemical Formula 17 as a colorless and clear liquid (23 g/yield: 90%).                           
     EXAMPLE 16 
     Synthesis of 5-norbornene-2-(3-hydroxy) cyclopentyloxymethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclopentanediol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 11, to obtain the compound of Chemical Formula 18 as a colorless and clear liquid (20 g/yield: 87%).                           
     EXAMPLE 17 
     Synthesis of 5-norbornene-2-(2-hydroxy) cyclopentyloxymethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,2-cyclopentanediol, 5-norbornene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the reaction mixture was worked up as in the procedure of Example 11, to obtain the compound of Chemical Formula 19 as a colorless and clear liquid (20.4 g/yield: 85%).                           
     EXAMPLE 18 
     Synthesis of oxabicyclo[2.2.1]-hept-5-ene-2-methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole) was dissolved in 300 ml of ethyl alcohol, and 0.1 mole of NaBH 4  was slowly added thereto at room temperature. After stirring for 1 hour, the reaction mixture was heated under reflux for 10 hours. After the reaction was completed, ethyl alcohol was distilled off. Acetone (200 ml) was added thereto, and the mixture was heated under reflux for 1 hour to remove excess NaBH 4 . After distilling off acetone, 100 ml of 10% hydrochloric acid was added to the residue, and the mixture was stirred for 10 minutes. Water (200 ml) and ethyl acetate (300 ml) were added thereto, and the mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate and filtered. After evaporation in vacuo by using a rotary evaporator, the residue was distilled under high vacuum, to obtain the compound of Chemical Formula 20 as a colorless and clear liquid (11 g/yield: 87%).                           
     EXAMPLE 19 
     Synthesis of oxabicyclo[2.2.1]-hept-5-ene-2-(1-methoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and methanol (500 ml) were reacted under reflux for 10 hours. Then, methanol was distilled off by using a rotary evaporator. To the reaction mixture, water (200 ml) and ethyl acetate (300 ml) were added, and the mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate and filtered. After evaporation in vacuo by using a rotary evaporator, the residue was distilled under high vacuum, to obtain the compound of Chemical Formula 21 as a colorless and clear liquid (13 g/yield: 93%).                           
     EXAMPLE 20 
     Synthesis of oxabicyclo[2.2.1]-hept-5-ene-2-(1-ethoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole) sulfuric acid (0.3 ml) and ethanol (500 ml) were reacted under reflux for 10 hours. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 22 as a colorless and clear liquid (13 g/yield: 91%)                           
     EXAMPLE 21 
     Synthesis of oxabicyclo[2.2.1]-hept-5-ene-2-(1-propoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole) sulfuric acid (0.3 ml) and propanol (500 ml) were reacted under reflux for 10 hours. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 23 as a colorless and clear liquid (17 g/yield: 91%)                           
     EXAMPLE 22 
     Synthesis of oxabicyclo2.2.1]hept-5-ene-2-(2-hydroxyethoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and ethylene glycol (100 ml) were reacted under reflux at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 24 as a colorless and clear liquid (16 g/yield: 89%)                           
     EXAMPLE 23 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(3-hydroxypropoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and trimethylene glycol (100 ml) were reacted under reflux for 12 hours at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 25 as a colorless and clear liquid (17 g/yield: 85%).                           
     EXAMPLE 24 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(4-hydroxybutoxy methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and 1,4-butanediol (100 ml) were reacted under reflux for 12 hours at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 26 as a colorless and clear liquid (18 g/yield: 86%)                           
     EXAMPLE 25 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(5-hydroxypentoxy)methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and 1,5-pentanediol (100 ml) were reacted under reflux for 12 hours at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 27 as a colorless and clear liquid (19 g/yield: 83%)                           
     EXAMPLE 26 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-[2-(2′-hydroxyethoxy)ethoxy]methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and diethylene glycol (100 ml) were reacted under reflux for 12 hours at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 28 as a colorless and clear liquid (20 g/yield: 85%)                           
     EXAMPLE 27 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-{2-[2-(2′2″-hydroxyethoxy)ethoxy]ethoxy}methanol 
     Oxabicyclo[2.2.1]hept-5-ene-2-carboxaldehyde (0.1 mole), sulfuric acid (0.3 ml) and triethylene glycol (100 ml) were reacted under reflux for 12 hours at 80° C. After the reaction was completed, the procedure of Example 19 was repeated to obtain the compound of Chemical Formula 29 as a colorless and clear liquid (22 g/yield: 85%)                           
     EXAMPLE 28 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-[(4-hydroxymethyl cyclohexyl)methoxy]methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,4-cyclohexanedimethanol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (200 ml) and ethyl acetate (500 ml) was added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo by using a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 30 as a colorless and clear liquid (25 g/yield: 93%).                           
     EXAMPLE 29 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-[(3-hydroxymethyl cyclohexyl)methoxylmethanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclohexanedimethanol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (200 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo by using a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 31 as a colorless and clear liquid (24 g/yield: 91%).                           
     EXAMPLE 30 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(3-hydroxycyclohexyloxy)methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclohexanediol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (200 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo by using a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 32 as a colorless and clear liquid (yield: 88%).                           
     EXAMPLE 31 
     Synthesis of oxabicyclo2.2.1]hept-5-ene-2-(4-hydroxycyclohexyloxy)methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,4-cyclohexanediol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. To the solution, water (200 ml) and ethyl acetate (500 ml) were added, and the resultant mixture was extracted. After washing with water (300 ml) once more, the organic layer was dried over anhydrous magnesium sulfate, filtered and evaporated in vacuo by using a rotary evaporator. The residue was distilled under high vacuum, to obtain the compound of Chemical Formula 33 as a colorless and clear liquid (22 g/yield: 92%).                           
     EXAMPLE 32 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-[(3-hydroxymethyl cyclopentyl)methoxy]methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclopentanedimethanol, oxabicyclo [2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the procedure of Example 28 was repeated to obtain the compound of Chemical Formula 34 as a colorless and clear liquid (23 g/yield: 90%).                           
     EXAMPLE 33 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-[(2-hydroxymethyl cyclopentyl)methoxy]methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,2-cyclopentanedimethanol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the procedure of Example 28 was repeated to obtain the compound represented by following Chemical Formula 35 as a colorless and clear liquid (23 g/yield: 90%).                           
     EXAMPLE 34 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(3-hydroxycyclopentyloxy)methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,3-cyclopentanediol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the procedure of Example 28 was repeated to obtain the compound represented by following Chemical Formula 36 as a colorless and clear liquid (20 g/yield: 87%).                           
     EXAMPLE 35 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-(2-hydroxycyclopentyloxy)methanol 
     To a solution of sodium hydride (0.1 mole) in 100 ml of 1,2-cyclopentanediol, oxabicyclo[2.2.1]-hept-5-ene-2-carboxaldehyde (0.1 mole) was slowly added at room temperature, and the mixture was reacted at the same temperature for 10 hours. After the reaction was completed, the procedure of Example 28 was repeated to obtain the compound represented by following Chemical Formula 37 as a colorless and clear liquid (20.4 g/yield: 85%).                           
     EXAMPLE 36 
     Synthesis of 5-norbornene-2-di(2-hydroxyethoxy) methane 
     The procedure of Example 4 was repeated but using twice as many moles of ethylene glycol to obtain the compound represented by the following Chemical Formula 38 as a colorless and clear liquid.                           
     EXAMPLE 37 
     Synthesis of 5-norbornene-2-di(3-hydroxypropoxy) methane 
     The procedure of Example 5 was repeated but using twice as many moles of trimethylene glycol to obtain the compound represented by following Chemical Formula 39 as a colorless and clear liquid.                           
     EXAMPLE 38 
     Synthesis of 5-norbornene-2-di(4-hydroxybutoxy) methane 
     The procedure of Example 6 was repeated but using twice as many moles of 1,4-butanediol to obtain the compound represented by following Chemical Formula 40 as a colorless and clear liquid.                           
     EXAMPLE 39 
     Synthesis of 5-norbornene-2-di(5-hydroxypentoxy) methane 
     The procedure of Example 7 was repeated but using twice as many moles of 1,5-pentanediol to obtain the compound represented by following Chemical Formula 41 as a colorless and clear liquid.                           
     EXAMPLE 40 
     Synthesis of 5-norbornene-2-di[2-(2′-hydroxyethoxy)ethoxy]methane 
     The procedure of Example 8 was repeated but using twice as many moles of diethylene glycol to obtain the compound represented by following Chemical Formula 42 as a colorless and clear liquid.                           
     EXAMPLE 41 
     Synthesis of 5-norbornene-2-di{2-[2′-(2″-hydroxyethoxy)ethoxy]ethoxy} methane 
     The procedure of Example 9 was repeated but using twice as many moles of triethylene glycol to obtain the compound represented by following Chemical Formula 43 as a colorless and clear liquid.                           
     EXAMPLE 42 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-di(2-hydroxyethoxy) methane 
     The procedure of Example 22 was repeated but using twice as many moles of ethylene glycol to obtain the compound represented by following Chemical Formula 44 as a colorless and clear liquid.                           
     EXAMPLE 43 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-di(3-hydroxypropoxy) methane 
     The procedure of Example 23 was repeated but using twice as many moles of trimethylene glycol to obtain the compound represented by following Chemical Formula 45 as a colorless and clear liquid.                           
     EXAMPLE 44 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-di(4-hydroxybutoxy) methane 
     The procedure of Example 24 was repeated but using twice as many moles of 1,4-butanediol to obtain the compound represented by following Chemical Formula 46 as a colorless and clear liquid.                           
     EXAMPLE 45 
     Synthesis of oxabicyclo [2.2.1]hept-5-ene-2-di(5-hydroxypentoxy) methane 
     The procedure of Example 25 was repeated but using twice as many moles of 1,5-pentanediol to obtain the compound represented by following Chemical Formula 47 as a colorless and clear liquid.                           
     EXAMPLE 46 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-di[2-(2′-hydroxyethoxy)ethoxy] methane 
     The procedure of Example 26 was repeated but using twice as many moles of diethylene glycol to obtain the compound represented by following Chemical Formula 48 as a colorless and clear liquid.                           
     EXAMPLE 47 
     Synthesis of oxabicyclo[2.2.1]hept-5-ene-2-di {2-[2′-(2″-hydroxyethoxy)ethoxy]ethoxy} methane 
     The procedure of Example 27 was repeated but using twice as many moles of triethylene glycol to obtain the compound represented by following Chemical Formula 49 as a colorless and clear liquid.