These common heterocyclic compound, 63666-11-5, name is Ethyl 5-amino-4H-[1,2,4]triazole-3-carboxylate, its 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. name: Ethyl 5-amino-4H-[1,2,4]triazole-3-carboxylate
Method A. To a suspension of 2-(2,3-dihydro-l -benzofuran-5-yl)-l,3-thiazole-4-carboxylic acid (381 mg, 1.54 mmol) and ethyl 5-amino-l,2,4-triazole-3-carboxylate (219 mg, 1.54 mmol) in 5.4 ml dry pyridine at boiling 2-(lH-benzotriazole-l-yl)-l,l53,3-tetramethyluronium hexafluorophosphate (HBTU) (643 mg, 1.70 mmol) was added in portions while solid dissolves gradually; clear solution forms 5 minutes after all 2-(lH-benzotriazole-l-yl)~l, 1,3,3- tetramethyluronium hexafluorophosphate (HBTU) was added. The solution war kept at stirring at 80 C during 15 h. Pyridine was evaporated to dryness, residue was washed with water, an aqueous NaHC03 solution, water, diluted aqueous AcOH and again water. The residue was dissolved in hot N,N-dimethylfonriamide, filtered, filtrate was evaporated to dryness, the residue was treated with boiling ethanol, cooled and filtered off. The procedure was repeated twice after which the residue was washed with ether and dried to give (339 mg, 0.88 mmol, 57 %) pure product. lE NMR (400 MHz, DMSO-c) delta ppm 14.16 (s, 1H, NH), 11.95 (s, 1H, NH), 8.46 (s, 1H, CH-thiazole), 8.08 (s, 1H, CH-Ar), 7.88 (d, J = 8.2 Hz, 1H, CH-Ar), 6.84 (d, J = 8.3 Hz, 1H, CH-Ar), 4.65 (t, J = 8.7 Hz, 2H, OCH2CH2), 4.34 (q, J = 7.0 Hz, 2H, OCH2CH3), 3.30 (t, J = 8.7 Hz, 1H, OCH2CH2), 1.37 (t, J = 7.1 Hz, 3H, OCCH3). LC/MS [M+H]+: 386.0
The synthetic route of Ethyl 5-amino-4H-[1,2,4]triazole-3-carboxylate has been constantly updated, and we look forward to future research findings.
Reference:
Patent; 4SC DISCOVERY GMBH; LEBAN, Johann; ZAJA, Mirko; WO2014/202638; (2014); A1;,
1,2,3-Triazole – Wikipedia,
Triazoles – an overview | ScienceDirect Topics