1 4 cyclohexanedione

Example 5

A 30-liter flask was charged with 1.44 kg of 1,4-cyclohexanedione (reagent available from Tokyo Chemical Industry Co., Ltd.), 3.53 kg of trimethylolpropane (available from Mitsubishi Gas Chemical Co., Inc.), 17.2 kg of ion exchanged water (20 mass % equivalent relative to the theoretical yield of the compound A), and 24.7 g of methanesulfonic acid (reagent available from Tokyo Chemical Industry Co., Ltd.), and the mixture was heated and stirred under normal pressure such that the temperature inside the flask was 40° C. to 50° C. and a cyclodehydration reaction was carried out. At the initial stage of the reaction, all of the raw materials were completely dissolved, and a clear and homogeneous solution was formed, but as the reaction proceeded, the product began to precipitate in a slurry form. The slurry liquid was then heated and stirred at that temperature for 8 hours. After the reaction slurry liquid was cooled to 25° C., the product was collected as a wet cake through a filtration operation. The obtained wet cake was neutralized by passing aqueous caustic soda through the wet cake, after which the wet cake was rinsed with water and vacuum dried, and thereby 2.34 kg of the compound A (GC purity: 99.2%, isolation yield: 52%) was obtained.

Example 8

A 100 mL round bottom flask was charged with 1.51 g of 1,4-cyclohexanedione (reagent available from Tokyo Chemical Industry Co., Ltd.), 5.0 g of α,α,α-tris(hydroxymethyl)toluene (available from Toronto Research Chemicals Inc.), 6.0 g of ion exchanged water, and 0.04 g of methanesulfonic acid (reagent available from Tokyo Chemical Industry Co., Ltd.), and the mixture was heated and stirred under normal pressure such that the temperature inside the flask was 25° C. to 30° C. and a cyclodehydration reaction was carried out. At the initial stage of the reaction, all of the raw materials were completely dissolved, and a clear and homogeneous solution was formed, but as the reaction proceeded, the product began to precipitate in a slurry form. The slurry liquid was then heated and stirred at that temperature for 24 hours. After the reaction slurry liquid was cooled to 25° C., the product was collected as a wet cake through a filtration operation. Furthermore, the reaction solution contained in the wet cake was flushed with 30 g of water. The obtained wet cake was neutralized by passing aqueous caustic soda through the wet cake, after which the wet cake was rinsed with water and vacuum dried, and thereby 2.7 g of a compound D (HPLC purity: 60%, isolation yield: 27%) was obtained.

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Example 7

A 1-liter round bottom separable flask was charged with 10 g of 1,4-cyclohexanedione (reagent available from Tokyo Chemical Industry Co., Ltd.), 25 g of trimethylolpropane (available from Mitsubishi Gas Chemical Co., Inc.), 580 g of ion exchanged water (5 mass % equivalent relative to the theoretical yield of the compound A), and 0.17 g of methanesulfonic acid (reagent available from Tokyo Chemical Industry Co., Ltd.), and the mixture was heated and stirred under normal pressure such that the temperature inside the flask was 40° C. to 50° C. and a cyclodehydration reaction was carried out. After all the raw materials were completely dissolved to form a clear and homogeneous solution, the solution was subsequently heated and stirred for 20 hours, but almost no slurry was produced. The reaction solution was then subjected to GC analysis, and production of the compound A (GC yield: 18.0%) was confirmed.