Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 3994-50-1, name is 1-Methyl-4-nitro-1H-pyrazole, A new synthetic method of this compound is introduced below., Recommanded Product: 3994-50-1
Example 25Synthesis of 4-[2-(difluoromethyl)-1H-benzimidazol-1-yl]-N-(1-methyl-1H-pyrazol-4-yl)-6-(4-morpholinyl)-1,3,5-triazin-2-amineThe compound was synthesized according to Method A.A mixture of 0.996 g (8.82 mmol) of 4-nitropyrazole (J. Med. Chem. 2005, 48, 5780-5793) and 1.33 g (10.6 mmol) of dimethyl sulphate in 10 mL of 1 M NaOH was heated at 35 C. for 48 hrs. The reaction mixture was cooled to RT and the precipitate was filtered, washed with water, and dried to give 0.561 g (50% yield) of 1-methyl-4-nitro-1H-pyrazole: 1H NMR (DMSO-d6) delta8.83 (s, 1H), 8.22 (s, 1H), 3.91 (s, 3H).A mixture of 0.144 g (1.14 mmol) 1-methyl-4-nitro-1H-pyrazole, 0.017 g (0.07 mmol) platinum oxide, and ethyl acetate (5 mL) in ethanol (15 mL) was stirred under 2 atmospheres of hydrogen for 14 hrs. The catalyst was removed by filtration through a pad of celite and the solvent was removed to give 0.080 mg (73% yield) of 4-amino-1-methyl-1H-pyrazole as a purple residue, which was used in the next step without further purification: 1H NMR (DMSO-d6) delta6.98 (s, 1H), 6.88 (s, 1H), 3.76 (br s, 2H), 3.65 (s, 3H).A mixture of 0.405 g (4.27 mmol) of 4-amino-1-methylpyrazole and 0.695 g (1.90 mmol) of 1-[4-chloro-6-(4-morpholinyl)-1,3,5-triazin-2-yl]-2-(difluoromethyl)-1H-benzimidazole in DMSO (5 mL) was heated at 125 C. for 15 min. The reaction mixture was cooled to room temperature and water was added. The solid was collected by filtration, washed with water, and dried. Chromatography on alumina, eluting with hexanes/EtOAc (1:1) gave a brown powder. Recrystallization from ethanol/CH2Cl2 gave 0.145 g (18% yield) of 4-[2-(difluoromethyl)-1H-benzimidazol-1-yl]-N-(1-methyl-1H-pyrazol-4-yl)-6-(4-morpholinyl)-1,3,5-triazin-2-amine: mp 225-226 C.; 1H NMR (DMSO-d6) (rotamers) delta10.00 (s, 1H), 9.73 (s, 0.2H), 8.60 (d, J=8.0 Hz, 1H), 8.29 (d, J=7.6 Hz, 0.2H), 7.92 (t, JHF=52.8 Hz, 1H), 7.86-7.80 (m, 2.6H), 7.68 (t, JHF=52.6 Hz, 0.2H), 7.59 (s, 1H), 7.52-7.42 (m, 2.9H), 3.85-3.82 (m, 8.4H), 3.75-3.73 (m, 4.8H); Anal. Calcd. for C19H19F2N9O 0.06EtOAc 0.24H2O: C, 52.9; H, 4.6; N, 28.8. Found: C, 52.9; H, 4.5; N, 28.6%.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; Pathway Therapeutics Limited; US2011/9405; (2011); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics