Synthesis
The general procedure for the synthesis of 1-(1-methyl-4-piperidinyl)-1H-pyrazol-4-amine from the compound (CAS:1201935-35-4) was as follows: 10% Pd-C catalyst (0.1 g) was added to a solution of compound 64-b (500 mg, 2.38 mmol) in ethanol (10 mL) under an atmosphere of hydrogen (1 atm). The reaction mixture was stirred at 25 °C for 16 hours. After completion of the reaction, the catalyst was removed by filtration and the filtrate was concentrated under reduced pressure to give the reddish brown oily product 64-a (420 mg, yield: 98%). The product could be used directly in the subsequent reaction without further purification. m/z = 181 [M + H]+ from LC-MS (ESI) analysis.
References
[1] Patent: US2015/336982, 2015, A1. Location in patent: Paragraph 0401; 0403
[2] Patent: WO2015/25197, 2015, A1. Location in patent: Paragraph 00075
[3] Patent: WO2009/153589, 2009, A1. Location in patent: Page/Page column 109
[4] Patent: US2010/317680, 2010, A1
[5] Patent: US2018/208604, 2018, A1. Location in patent: Paragraph 0339-0340
