1. 407 g of xylene and 7.63 g (0.045 mol) of copper chloride dihydrate are added to a 2 L separable flask, a double star blade and bar baffle are fitted and the flask is placed on a water bath.
2. a reflux condenser (with cooling tubes) and a dropping funnel are configured with 254 g (1.02 mol) of triallyl 1,3,5-trimellitic acid and 102 g of xylene, attached to a separable flask. The unit is equipped with a tee plug for nitrogen sealing the remaining ports and fitted with a thermometer.
3. Nitrogen seal through the top of the condenser, displace the inside of the separable flask and the inside of the dropping funnel with nitrogen three times to ensure that the oxygen concentration is less than 0.3 vol%, and start stirring (508 rpm).
4. Raise the temperature of the water bath to control the internal temperature at 65°C and add half of the feedstock dropwise. After about 90 minutes, the heat of the reaction causes the temperature to rise to 100°C, and the temperature drops to 75°C as the reaction nears completion.
5. At the end of the reaction or at a lower temperature, the remaining feedstock was added. After about 120 minutes, exotherm was observed with a peak temperature of 98°C. Stirring was continued for 20 minutes after exotherm.
6. xylene was distilled from the reaction solution and filtered using a Kiriyama funnel to give an oily product. Gas chromatographic analysis showed 99.7% purity and 90% yield of 1,3-diallyl-1,3,5-triazine-2,4,6-trione.
7. In another experiment, 61 g (1.02 mol) of acetic acid was added to the dropping funnel as in steps 1-6. After the reaction was completed and cooled to 40 °C, 127 g of water was added to completely precipitate 1,3-diallyl-1,3,5-triazine-2,4,6-trione.
8. The mixture was filtered using a Kiriyama funnel and the filter cake was washed with 127 g of toluene and 127 g of water. The solid product was placed in a vacuum desiccator and dried at 70 °C for 7 h at a pressure of less than 1,000 Pa. Gas chromatographic analysis showed a product purity of 99.9% and a yield of 90%.
9. In another experiment, the reaction temperature was set to 60 °C, the raw material in the dropping funnel was added at once, and the rest was the same as steps 7-8. Gas chromatographic analysis showed that the product purity was 99.9% and the yield was 92%.
