With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.21043-40-3,1-Cyclopentylpiperazine,as a common compound, the synthetic route is as follows.
A mixture of 2 g (14 mmol) 6-chloronicotinonitrile (commercially available) 2.45 g (16 mmol) N-cyclopentylpiperazine (commercially available) and 1.86 g (14 mmol) N,N-diisopropylethylamine in 5 ml water and 15 ml DMF was heated to 90 C. for 24 h. After addition of 250 ml 1M NaHCO3 aq. solution the mixture was extracted three times with 250 ml ethyl acetate each. The combined organic phases were washed twice with 150 ml brine each, dried and evaporated to dryness. Recrystallization from ethyl acetate yielded a first batch of 2.83 g of white crystals. An additional batch was yielded from the filtrate and in total 3.14 g (85%)n of the title compound was obtained as white crystals. (m/e): 257.1 (MH+; 100%).
21043-40-3, As the paragraph descriping shows that 21043-40-3 is playing an increasingly important role.
Reference：
Patent; Nettekoven, Matthias Heinrich; Roche, Olivier; Rodriguez-Sarmiento, Rosa Maria; US2006/122187; (2006); A1;,
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