Electric Literature of 57999-06-1,Some common heterocyclic compound, 57999-06-1, name is 4-Phenyl-1H-pyrazol-5-amine, molecular formula is C9H9N3, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
[00237] Sodium metal (0.64g, 28mmol) was washed with petrol, and then cut into small pieces. The pieces were added to dry toluene (5ml). More dry toluene (5ml) and EtOAc (3.7ml, 38mmol) were added, followed by ethyl formate (0.64ml, 8mmol) dropwise. The mixture was heated at 5O0C for 20 minutes, then cooled to room temperature and stirred for 30 minutes. Additional ethyl formate (ImI, 12.5mmol) was added dropwise, and the mixture stirred at room temperature for 1 hour. A final batch of ethyl formate (ImI, 12.5mmol) was added dropwise, and the mixture stirred at room temperature overnight. The mixture was then diluted with dry EtOH (200ml), and 4-phenyl-lH-pyrazol-5 -amine (2g, 12.6mmol) was added. The mixture was heated under reflux overnight. The mixture was cooled and concentrated. The solid residue was dissolved in hot water and filtered. The filtrate was acidified with cone. HCl until pHl. The precipitate was then filtered off, washed with ether, and dried in vacuo to yield 1.4g (52.7%) of the title compound. 1H NMR (d6-DMSO): 12.30 (IH, d, J 4.3), 8.23 (IH, s), 7.82 (IH, t, J 7.0), 7.60 (2H, d, J 7.1), 7.46 (2H, d, J 7.9), 7.30 (lH, t, J7.4), 5.79 (IH, d, J7.3).
The synthetic route of 57999-06-1 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; BioMarin IGA, Ltd.; WREN, Stephen Paul; WYNNE, Graham Michael; LECCI, Cristina; WILSON, Francis Xavier; WO2010/86040; (2010); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics