13484-40-7

110-85-0

627-42-9

13484-40-7

13484-41-8

Under nitrogen protection, 8.6 g (0.1 mol) of piperazine and 10.4 g of methanol were added to the reaction flask, 35 µl of hydrochloric acid (10.4 g, 0.1 mol) was added with stirring, and the internal temperature was controlled to 80 °C. Under the condition of keeping the internal temperature below 80 °C, 8.7 g (0.07 mol) of 2-bromoethanol was added slowly and dropwise over 0.5 h. Subsequently, the reaction was continued with stirring at the same temperature for 8 h. 36.9 g of colorless and transparent reaction solution was obtained. Gas chromatographic analysis showed a yield of 84.6% for N-(2-hydroxyethyl)piperazine, with a selectivity of 88.5% for N-(2-hydroxyethyl)piperazine, 7.7% for N,N'-bis(2-hydroxyethyl)piperazine, and 3.8% for the unknown component. Compared to the results of Example 2 in Table 1 , the reaction conditions were the same as in Example 2 when 3.8 g (0.04 mol) of 2-methoxyethyl ester was used in place of 2-bromoethanol. GC analysis showed a 70.1% yield of N-(2-methoxyethyl)piperazine with a selectivity of 83.4% for N-(2-methoxyethyl)piperazine, 15.0% for N,N'-bis(2-methoxyethyl)piperazine, and 1.6% for the unknown component. This result is consistent with the results of Example 5 in Table 1.