Electric Literature of 23688-89-3, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 23688-89-3, name is 6-Chloropyrazine-2-carboxylic acid belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.
A mixture of Compound 3A (220 mg, 1.39 mmol; prepared as described in Sato, N. J. Heterocyc. Chem. 1994,31, 1177), DPPA (575 mg, 2.09 mmol) and triethylamine (0. [39] [ML,] 2. 80 mmol) in [T-BUOH] (3 mL) and toluene (2 mL) was heated at [65 C] for 1.5 h, then at [85 C] for 2 h. After concentration, the mixture was purified by flash chromatography (EtOAc/hexane) to give Compound 3B (180 mg, 57%) as a white [SOLID. 1H NMR] (300 MHz, CDC13) 8 [9. 19 (S,] 1H), 8.26 (s, 1H), 7.17 (brs, 1H), 1.54 (s, 9H). A mixture of Compound 3B (160 mg, 0.697 mmol), [(3-BROMOPROPOXY)-TERT-] butyldimethylsilane (220 mg, 0.870 mmol) and [CS2CO3] (340 mg, 1.04 mmol) in dry DMF (2 mL) was stirred at [60 C] for 2.5 h. The solvent was evaporated under reduced pressure and the residue was purified by column chromatography (EtOAc/hexane) to provide Compound 3C (262 mg, 94%) as clear [OIL. LH NMR (300 MHZ, CDC13) 6 9.] 01 (s, 1H), 8.20 (s, 1H), 4.00 (t, J= 7.4 Hz, 2H), 3. 68 (t, J= [6.] 2 Hz, 2H), 1.87 [(M,] 2H), 1.54 (s, 9H), 0.87 (s, 9H), 0.03 (s, 6H). A mixture of Compound 3C (123 mg, 0.306 mmol), bis [(TRIMETHYLTIN)] (200 mg, 0.611 mmol), tetrakis (triphenylphosphine) palladium (35 mg, 0.030 mmol), LiCl (40 mg, 0.94 mmol) and 2, 6-di-tert-butyl-4-methylphenol (3 mg, 0.014 mmol) in anhydrous 1,4- dioxane (2 [ML)] was refluxed for 4 h under nitrogen. The solvent was removed under reduced pressure and the residue was purified by chromatography on silica gel (EtOAc/hexane) to give Compound 3D (154 mg, 95%) as clear [OIL. 1H NMR] (300 MHz, CDC13) 8 8.79 (s, 1H), 8.21 (s, [1H),] 4.01 (t, J= 7.2 Hz, 2H), 3.67 (t, J= 6.0 Hz, 2H), 1.90 [(M,] 2H), 1.53 (s, 9H), 0. 87 (s, 9H), 0.36 (s, 9H), 0.02 (s, 6H); MS (ES) m/z : 531 (M+H). A mixture of Compound 3D (73 mg, 0.14 [MMOL),] Compound 1C (52 mg, 0.15 mmol), dichlorobis (triphenylphosphine) palladium (15 mg, 0.021 mmol) and LiCl (18 mg, 0.42 mmol) in anhydrous toluene (3 mL) was stirred at [100 C] overnight under nitrogen. The mixture was cooled, concentrated under vacuum and purified by flash chromatography (EtOAc/hexane) to give the coupled product as yellow oil. TFA (1 mL) was added and the mixture was stirred at [20 C] for 4 h. After it was concentrated, saturated NH40H solution and water were added until the mixture turned basic. After the precipitated solid was collected through filtration, it was washed with water and [ET20] and dried under vacuum to provide Compound 3 (1.5 mg, 47%) as a yellow solid. [H NMR] (300 MHz, DMSO-d6) [6] 10.59 (s, 1H), 8.91 (s, 1H), 8.63 (s, 1H), 8.20 (brs, 1H), 8.12 (s, 1H), 7.80 (brs, 1H), 7.39 (t, J= 8.2 Hz, 1H), 7.34 (brs, 1H), 7.13 [(D,] [J=] 7.8 Hz, 1H), 4.60 [(M,] 1H), 3.50 [(M,] 2H), 3.32 [(M,] 2H), 1.76 (t, J= 6.4 Hz, [2H) ;] MS (ES) m/z: 358 [(M+H.]
The synthetic route of 6-Chloropyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.
Reference:
Patent; JANSSEN PHARMACEUTICA, NV; KUO, Gee-Hong; DEANGELIS, Alan; WANG, Aihua; ZHANG, Yan; EMANUEL, Stuart, L.; MIDDLETON, Steve, A.; WO2004/9562; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem