Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 21943-13-5, name is 5-Bromo-3-chloropyrazin-2-amine, A new synthetic method of this compound is introduced below., Application In Synthesis of 5-Bromo-3-chloropyrazin-2-amine
A solution of 55 (9.00 g, 43.2 mmol) in concentrated sulfuric acid (35 mL) was added dropwise at 0 C to a solution of sodium nitrite (3.52 g, 51.0 mmol) in concentrated sulfuric acid (20 mL). The solution was heated at 40 C for 1 h, then cooled to rt and poured onto crushed ice (400 mL). The mixture was extracted with ethyl acetate (200 mL). The extract was dried, filtered and concentrated to give 56 (6.13 g, 68%) as a brown solid. Mp 175-177 C; numax/cm-1 3019 (ArH), 1653 (C=O); deltaH (500 MHz; CD3OD) 7.72 (1H, s, 6-H); deltaC (125 MHz; CDCl3) 114.2, 127.6, 146.4, 154.0; LC-MS (6 min) m/z 213, 211, 209 (MH+); HPLC tR 2.54 min purity >99%; HRMS (found: MH+ m/z 208.9113; requires 208.9112).
The synthetic route of 21943-13-5 has been constantly updated, and we look forward to future research findings.
Reference:
Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728,16;; ; Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728;,
Pyrazine – Wikipedia,
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