Application of 37622-90-5,Some common heterocyclic compound, 37622-90-5, name is Ethyl 4-pyrazolecarboxylate, molecular formula is C6H8N2O2, 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.
Under anhydrous condition, to a solution of ethyl 4-pyrazolecarboxylate (600 mg) in DMF (21ml, c=0.1 molL-1) cooled by an ice bath, NaH (in mineral oil 60%, 225 mg, 1.3 equiv.) was added in 3 portions (over 5 minutes). The mixture was stirred for 15 minutes, then methyl iodide (410 muL, 1.2 equiv.) was added. The ice bath was removed and the reaction was stirred at room temperature for 1 Hrs. The mixture was hydrolysed with a saturated aqueous solution of NaHCO3 (200 ml) and extracted twice with EtOAc (2*250 ml). The organic layers were combined, washed with brine (400 ml), dried over MgSO4 and concentrated. Purification by flash-chromatography (AcOEt in cyclohexane, 5 to 100%) afforded compound 107 as a colourless oil in 90% yield. 1H-NMR (400 MHz, DMSO): 1.26 (t, J 7.1 Hz, 3H, O-CHrCH3); 1.38 (t, J 7.3 Hz, 3H, N-CHrCH3); 4.17 (q, J 7.3 Hz, 2H, N-CH2-CH3); 4.21 (q, J 7.1 Hz, 2H, O-CH2-CH3); 7.84 (s, 1H, Ar);8.33 (s, 1H, Ar). M/Z (M+H)+ = 169.0.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 4-pyrazolecarboxylate, its application will become more common.
Reference:
Patent; DOMAIN THERAPEUTICS; MAYER, Stanislas; SCHANN, Stephan; WO2013/174822; (2013); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics