With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.20327-23-5,1-Cyclopropylpiperazine,as a common compound, the synthetic route is as follows.
A solution of DIPEA (690 mul, 3.97 mmol) and 1-cyclopropylpiperazine (500 mg, 3.97 mmol) in acetonitrile (5 ml) was added to a solution of 2-chloro-5-nitropyridine (631 mg, 3.97 mmol) in acetonitrile (10 ml). The mixture was stirred at rt for 4 hours and then concentrated to dryness. The residue was diluted with DCM and 2M sodium carbonate solution (aq). The organic phase was dried and concentrated to give a yellow solid (912 mg, 93%). 1H NMR (400 MHz, DMSO-cfe) delta ppm 0.31 – 0.49 (m, 4 H), 1.65 (it, ./=6.70, 3.38 Hz, 1 H), 2.52 – 2.69 (m, 4 H), 3.61 – 3.82 (m, 4 H), 6.95 (d, 7=9.62 Hz, 1 H), 8.21 (dd, 7=9.62, 2.75 Hz, 1 H), 8.95 (d, 7=2.75 Hz, 1 H); m/z (ES+APCI)+: 249 [M+H]+., 20327-23-5
As the paragraph descriping shows that 20327-23-5 is playing an increasingly important role.
Reference：
Patent; MEDICAL RESEARCH COUNCIL; WO2009/122180; (2009); A1;,
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