6203-08-3

542-92-7

292638-85-8

6203-08-3

0.510 mol (68.0 g) of anhydrous aluminum chloride was suspended in 660 mL of toluene. 0.600 mol (51.7 g) methyl acrylate was added to the suspension and stirred until the aluminum chloride was completely dissolved. A solution of 0.600 mol (39.7 g) of freshly cleaved cyclopentadiene dissolved in 340 mL of toluene was added dropwise to the solution over 45 minutes. The reaction mixture was stirred at room temperature for 90 minutes and subsequently poured into water. The toluene layer was separated, washed with water, dried over anhydrous sodium sulfate, filtered and concentrated to dryness under reduced pressure. Purification by vacuum distillation on a Vigreux column afforded methyl 5-norbornene-2-carboxylate in 66.3 g (74%) yield and 99% purity (GC). 5-Norbornene-2-carboxylic acid was prepared by mixing 164 mmol (25.0 g) of methyl ester with 85 g of 10% NaOH solution at 60°C until the ester layer disappeared. After cooling, it was washed with ether and acidified with 235 mL of 1 M hydrochloric acid at 60-70°C with stirring. The acid layer was separated, dissolved in ethyl acetate, washed with water, dried over anhydrous sodium sulfate, filtered and concentrated to dryness under reduced pressure to yield 18.2 g (80%).1H and 13C NMR confirmed the product as 5-norbornene-2-carboxylic acid. 132 mmol (18.2 g) of the acid was dissolved in 480 mL of dichloromethane and 2.66 mmol (0.205 mL) of N,N-dimethylformamide and 665 mmol (57.0 mL) of oxaloyl chloride were added dropwise over 1 hr. Stirred at room temperature for 1.5 h. The solvent and excess oxalyl chloride were removed by evaporation under reduced pressure to give a brown oil in a yield of 18.1 g (88%). 115 mmol (18.0 g) of chloroyl chloride was added to a mixture of diethylene glycol (57.5 mmol, 6.10 g) and pyridine (115 mmol, 9.09 g) and stirred at room temperature for 4 hours. 150 mL of dichloromethane and 100 mL of water were added, the organic layer was washed sequentially with water, sodium bicarbonate solution and hydrochloric acid solution, dried over anhydrous sodium sulfate, filtered, and concentrated to dryness to give a yellow oil in a yield of 18.9 g (95%).1H and 13C NMR showed that the product was predominantly a diester. Diethylene glycol di(5,6-epoxy-2-norbornanecarboxylate) was prepared by dissolving 54.5 mmol (18.9 g) of the diester in 260 mL of dichloromethane. Another 15.3 mmol (2.08 g) of sodium acetate trihydrate was dissolved in a 39% peracetic acid solution of acetic acid (153 mmol, 29.8 g) and added dropwise to the diester solution over 30 minutes. The reaction mixture was stirred at room temperature for 4 h. The reaction mixture was washed with water and sodium bicarbonate solution, the organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated to dryness to give light yellow oily diethylene glycol bis(5,6-epoxy-2-norbornanecarboxylate) in a yield of 19.8 g (96%) and purity of 94% (GC). The structure of the product was confirmed by 1H and 13C NMR.