Reference of 36070-83-4, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 36070-83-4 name is Ethyl 5-bromopyrazine-2-carboxylate, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.
Embodiment 66 ethyl 5-((4,4-dimethylthiochroman-6-yl)ethynyl)pyrazin-2-carboxylate ethyl 5-bromopyridazin-2-carboxylate (600mg, 2.61mmol) and 6-ethynyl-4,4-dimethylbenzothiopyran (635mg, 3.13mmol) were added to a flask, followed by addition of Pd(PPh3)2Cl2 (66mg, 0.094mmol) and CuI (36mg, 0.188mmol). After the flask was purged with argon for 3 times to remove oxygen, 6mL dry DMF and 0.4mL dry Et3N were added via syringe. Then the reaction was continued at 80C for 8 h and monitored by TLC. After completion of the reaction, the reaction was quenched with saturated ammonium chloride solution. The mixture was diluted with ethyl acetate, washed with saturated ammonium chloride solution and saturated sodium chloride solution. The organic phase was dried over anhydrous sodium sulfate, filtered, concentrated and purified by flash column chromatography (PE:EtOAc = 50:1) to give WYC-322 (656mg, 71.5%). 1H NMR (500 MHz, CDCl3) delta 9.20 (d, J = 1.4 Hz, 1H), 8.76 (d, J = 1.4 Hz, 1H), 7.58 (d, J = 1.7 Hz, 1H), 7.23 (dd, J = 8.2, 1.8 Hz, 1H), 7.04 (d, J = 8.2 Hz, 1H), 4.46 (q, J = 7.1 Hz, 2H), 3.02 – 2.97 (m, 2H), 1.92 – 1.87 (m, 2H), 1.41 (t, J = 7.1 Hz, 3H), 1.29 (s, 6H). 13C NMR (126 MHz,CDCl3) delta 163.65, 146.68, 145.70, 143.08, 142.31, 140.30, 136.14, 130.54, 129.51, 126.74, 116.00, 97.55, 85.68, 62.37, 36.91, 32.99, 29.89, 23.27, 14.31. ESI(+)-MS: 353.5 [M+1]+.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, Ethyl 5-bromopyrazine-2-carboxylate, and friends who are interested can also refer to it.
Reference:
Patent; Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences; Huazhong University of Science and Technology; CAO, Xin; YU, Biao; WANG, Ning; CHEN, Junwei; (88 pag.)EP3428155; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem